Leptin as a Biomarker of Stress: A Systematic Review and Meta-Analysis

Background: Leptin is a satiety hormone mainly produced by white adipose tissue. Decreasing levels have been described following acute stress. Objective: To conduct a systematic review and meta-analysis to determine if leptin can be a biomarker of stress, with levels decreasing following acute stress. Methods: PubMed, Cochrane Library, Embase, and ScienceDirect were searched to obtain all articles studying leptin levels after acute stress on 15 February 2021. We included articles reporting leptin levels before and after acute stress (physical or psychological) and conducted random effects meta-analysis (DerSimonian and Laird approach). We conducted Meta-regressions and sensitivity analyses after exclusion of groups outside the metafunnel. Results: We included seven articles—four cohort and three case-control studies—(28 groups) from 27,983 putative articles. Leptin levels decreased after the stress intervention (effect size = −0.34, 95%CI −0.66 to −0.02) compared with baseline levels, with a greater decrease after 60 min compared to mean decrease (−0.45, −0.89 to −0.01) and in normal weight compared to overweight individuals (−0.79, −1.38 to −0.21). There was no difference in the overweight population. Sensitivity analyses demonstrated similar results. Levels of leptin after stress decreased with sex ratio—i.e., number of men/women—(−0.924, 95%CI −1.58 to −0.27) and increased with the baseline levels of leptin (0.039, 0.01 to 0.07). Conclusions: Leptin is a biomarker of stress, with a decrease following acute stress. Normal-weight individuals and women also have a higher variation of leptin levels after stress, suggesting that leptin may have implications in obesity development in response to stress in a sex-dependent manner.

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Ghrelin as a Biomarker of Stress: A Systematic Review and Meta-Analysis

Nutrients ◽

10.3390/nu13030784 ◽

2021 ◽

Vol 13 (3) ◽

pp. 784

Author(s):

Jean-Baptiste Bouillon-Minois ◽

Marion Trousselard ◽

David Thivel ◽

Brett Ashley Gordon ◽

Jeannot Schmidt ◽

...

Keyword(s):

Systematic Review ◽

Social Stress ◽

Acute Stress ◽

Meta Analysis ◽

Stress Test ◽

Trier Social Stress Test ◽

Cochrane Library ◽

Stress Intervention ◽

Before And After ◽

Seeking Behavior

Introduction: Ghrelin is an orexigenic hormone which favors food-seeking behavior and has been postulated to be a biomarker of stress. We conducted a systematic review and meta-analysis on the evolution of ghrelin levels following acute stress. Methods: The PubMed, Cochrane Library, Embase, and ScienceDirect databases were searched for studies reporting ghrelin levels before and after acute stress in humans. Results: We included ten studies for a total of 348 patients. Acute stress (intervention) was always in a laboratory. Acute stress was psychological (Trier Social Stress Test), physical, or mixed (cold pressure test). The overall meta-analysis demonstrated an increase in ghrelin after the stress intervention (ES = 0.21, 95CI 0.09 to 0.34) compared with baseline levels. Stratification by time demonstrated an acute increase in ghrelin levels in the five minutes immediately following the initiation of stress (0.29, 0.10 to 0.48) but without any difference after. Obese individuals had a more significant (ES = 0.51, 95CI 0.18 to 0.84) and prolonged increase in ghrelin levels for up to 45 min compared with non-obese individuals who had a significant increase only five minutes after stress. Moreover, the ghrelin levels increased in response to stress with BMI (coefficient 0.028, 0.01 to 0.49; p = 0.013) and decreased with the time after the stress intervention (coefficient -0.007, −0.014 to −0.001; p = 0.025). Conclusion: Ghrelin is a biomarker of stress, with a short-term increase following acute stress. Obese individuals have both a higher and prolonged response, emphasizing the link between obesity and stress.

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Does coffee, tea and caffeine consumption reduce the risk of incident breast cancer? A systematic review and network meta-analysis

Public Health Nutrition ◽

10.1017/s1368980021000720 ◽

2021 ◽

pp. 1-13

Author(s):

Shu Wang ◽

Xiang Li ◽

Yue Yang ◽

Jingping Xie ◽

Mingyue Liu ◽

...

Keyword(s):

Breast Cancer ◽

Systematic Review ◽

Postmenopausal Women ◽

Meta Analysis ◽

High Dose ◽

Dependent Manner ◽

Tea Consumption ◽

Case Control Studies ◽

High Concentration ◽

Coffee Intake

Abstract Objective: We aimed to evaluate the association between coffee and/or tea consumption and breast cancer (BC) risk among premenopausal and postmenopausal women and to conduct a network meta-analysis. Design: Systematic review and network meta-analysis. Setting: We conducted a systematic review of electronic publications in the last 30 years to identify case–control studies or prospective cohort studies that evaluated the effects of coffee and tea intake. Results: Forty-five studies that included more than 3 323 288 participants were eligible for analysis. Network meta-analysis was performed to determine the effects of coffee and/or tea consumption on reducing BC risk in a dose-dependent manner and differences in coffee/tea type, menopause status, hormone receptor and the BMI in subgroup and meta-regression analyses. According to the first pairwise meta-analysis, low-dose coffee intake and high-dose tea intake may exhibit efficacy in preventing ER(estrogen receptor)− BC, particularly in postmenopausal women. Then, we performed another pairwise and network meta-analysis and determined that the recommended daily doses were 2–3 cups/d of coffee or ≥5 cups/d of tea, which contained a high concentration of caffeine, particularly in postmenopausal women. Conclusions: Coffee and tea consumption is not associated with a reduction in the overall BC risk in postmenopausal women and is associated with a potentially lower risk of ER− BC. And the highest recommended dose is 2–3 cups of coffee/d or ≥5 cups of tea/d. They are potentially useful dietary protectants for preventing BC.

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DHEA as a Biomarker of Stress: A Systematic Review and Meta-Analysis

Frontiers in Psychiatry ◽

10.3389/fpsyt.2021.688367 ◽

2021 ◽

Vol 12 ◽

Author(s):

Frédéric Dutheil ◽

Sarah de Saint Vincent ◽

Bruno Pereira ◽

Jeannot Schmidt ◽

Farès Moustafa ◽

...

Keyword(s):

Systematic Review ◽

Mental Stress ◽

Acute Stress ◽

Meta Analysis ◽

Public Health Problem ◽

Cochrane Library ◽

Main Peak ◽

Significant Public Health Problem ◽

Significant Public Health ◽

Two Measures

Background: Psychosocial stress is a significant public health problem inducing consequences for quality of life. Results about the use of dehydroepiandrosterone (DHEA) as a biomarker of acute stress are conflicting. We conducted a systematic review and meta-analysis to demonstrate that DHEA levels could be a biomarker of stress.Methods: PubMed, Cochrane Library, Embase, and ScienceDirect databases were searched on March 19, 2021 using the keywords “acute stress” AND “DHEA” OR “Dehydroepiandrosterone.” Articles needed to describe our primary outcome, i.e., induction of acute stress and at least two measures of DHEA.Results: We included 14 studies, with a total of 631 participants, in our meta-analysis. The DHEA levels increased overtime after acute stress [standardized mean difference (SMD) = 1.56, 95%CI = 1.13–1.99]. Stratification by time showed a main peak at the end of stress (SMD = 2.43, 95%CI = 1.59–3.27), followed by a progressive decrease (coefficient = −0.11, 95%CI = −0.19 to −0.17, p = 0.020). There was no significant change 1 h after the end of acute stress. Metaregressions showed an impact of mental stress (SMD = 2.04, 95%CI = 1.43–2.65), sex (SMD = 0.02, 95%CI = 0.00–0.04), age (SMD = −0.12, 95%CI = −0.2 to −0.05), and obesity (SMD = 0.31, 95%CI = −0.00 to 0.63). There was no difference whatever the type of fluid (blood or saliva) and the measurement technique used.Conclusions: DHEA is a biomarker of acute stress, with a short-term increase (1 h). DHEA increases following acute mental stress, whatever the type and duration of mental stress. Women, young people, and obese individuals had a higher response. Blood and saliva measures were comparable.

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Incidence and trend of preterm birth in China, 1990–2016: a systematic review and meta-analysis

BMJ Open ◽

10.1136/bmjopen-2020-039303 ◽

2020 ◽

Vol 10 (12) ◽

pp. e039303

Author(s):

Shiwen Jing ◽

Chang Chen ◽

Yuexin Gan ◽

Joshua Vogel ◽

Jun Zhang

Keyword(s):

Systematic Review ◽

Preterm Birth ◽

Birth Rate ◽

Meta Analysis ◽

Northwest China ◽

Cochrane Library ◽

Case Control Studies ◽

Eligibility Criteria ◽

Rate Of Increase ◽

Preterm Birth Rate

ObjectivesTo update the WHO estimate of preterm birth rate in China in 1990–2016 and to further explore variations by geographic regions and years of occurrence.DesignSystematic review and meta-analysis.Data sourcesPubmed, Embase, Cochrane Library and Sinomed databases were searched from 1990 to 2018.Eligibility criteriaStudies were included if they provided preterm birth data with at least 500 total births. Reviews, case–control studies, intervention studies and studies with insufficient information or published before 1990 were excluded. We estimated pooled incidence of preterm birth by a random effects model, and preterm birth rate in different year, region and by livebirths or all births in subgroup analyses.ResultsOur search identified 3945 records. After the removal of duplicates and screening of titles and abstracts, we reviewed 254 studies in full text and excluded 182, leaving 72 new studies. They were combined with the 82 studies included in the WHO report (154 studies, 187 data sets in total for the meta-analysis), including 24 039 084 births from 1990 to 2016. The pooled incidence of preterm birth in China was 6.09% (95% CI 5.86% to 6.31%) but has been steadily increasing from 5.36% (95% CI 4.89% to 5.84%) in 1990–1994 to 7.04% (95% CI 6.09% to 7.99%) in 2015–2016. The annual rate of increase was about 1.05% (95% CI 0.85% to 1.21%). Northwest China appeared to have the highest preterm birth rate (7.3%, 95% CI 4.92% to 9.68% from 1990 to 2016).ConclusionsThe incidence of preterm birth in China has been rising gradually in the past three decades. It was 7% in 2016. Preterm birth rate varied by region with the West having the highest occurrence.

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Efficacy of zinc as adjunctive pneumonia treatment in children aged 2 to 60 months in low-income and middle-income countries: a systematic review and meta-analysis

BMJ Paediatrics Open ◽

10.1136/bmjpo-2020-000662 ◽

2020 ◽

Vol 4 (1) ◽

pp. e000662 ◽

Cited By ~ 1

Author(s):

Nick Brown ◽

Antti Juhani Kukka ◽

Andreas Mårtensson

Keyword(s):

Systematic Review ◽

Treatment Failure ◽

Low Income ◽

Meta Analysis ◽

Severe Pneumonia ◽

Risk Of Bias ◽

Sensitivity Analyses ◽

Cochrane Library ◽

Middle Income ◽

Middle Income Countries

BackgroundDespite advances in vaccination and case management, pneumonia remains the single largest contributor to early child mortality worldwide. Zinc has immune-enhancing properties, but its role in adjunctive treatment of pneumonia in low-income and middle-income countries (LMICs) is controversial and research still active.MethodsSystematic review and meta-analysis of randomised controlled trials of zinc and placebo in pneumonia in children aged 2 to 60 months in LMICs. Databases included MEDLINE, the Cochrane Library, EMBASE, LILACS, SciELO, the WHO portal, Scopus, Google Scholar and ClinicalTrials.gov. Inclusion criteria included accepted signs of pneumonia and clear measure of outcome. Risk of bias was independently assessed by two authors. ORs with 95% CI were used for calculating the pooled estimate of dichotomous outcomes including treatment failure and mortality. Time to recovery was expressed as HRs. Sensitivity analyses considering risk of bias and subgroup analyses for pneumonia severity were performed.ResultsWe identified 11 trials published between 2004 and 2019 fulfilling the a priori defined criteria, 7 from South Asia and 3 from Africa and 1 from South America. Proportional treatment failure was comparable in both zinc and placebo groups when analysed for all patients (OR 0.95 (95% CI 0.80 to 1.14)) and only for those with severe pneumonia (OR 0.93 (95% CI 0.75 to 1.14)). No difference was seen in mortality between zinc and placebo groups (OR 0.64 (95% CI 0.31 to 1.31)). Time to recovery from severe pneumonia did not differ between the treatment and control groups for patients with severe pneumonia (HR 1.01 (95% CI 0.89 to 1.14)). Removal of four studies with high risk of bias made no difference to the conclusions.ConclusionThere is no evidence that adjunctive zinc treatment improves recovery from pneumonia in children in LMICs.Trial registration numberCRD42019141602.

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Association between sepsis and retinopathy of prematurity: a systematic review and meta-analysis

BMJ Open ◽

10.1136/bmjopen-2018-025440 ◽

2019 ◽

Vol 9 (5) ◽

pp. e025440 ◽

Cited By ~ 3

Author(s):

Xiaofen Wang ◽

Kun Tang ◽

Ling Chen ◽

Sixiang Cheng ◽

Huilan Xu

Keyword(s):

Systematic Review ◽

Cohort Studies ◽

Premature Infants ◽

Retinopathy Of Prematurity ◽

Data Extraction ◽

Meta Analysis ◽

Cochrane Library ◽

Case Control Studies ◽

Severe Stage

ObjectiveTo explore the association between sepsis and retinopathy of prematurity (ROP) in premature infants.DesignA systematic review and meta-analysis.Data sourcesWe performed a systematic search of PubMed, the Cochrane Library and Embase from 1 January, 2000, to 1 January, 2018, with no language restrictions and reported the relationship between sepsis and ROP.Eligibility criteriaOriginal observational studies, including cohort studies and case-control studies.Data extraction and synthesisTwo reviewers independently completed the study selection and data extraction. The OR and corresponding 95% CI were used to measure the risk of sepsis in patients with ROP. The heterogeneity between studies was evaluated using Cochran’s Q test and the I2statistic. The Newcastle-Ottawa Scale was adopted to evaluate the quality of each of the included studies, and the Grading of Recommendations Assessment, Development and Evaluation approach was used to assess the quality of the evidence.ResultsSixteen studies with a total sample size of 12 466 premature infants and 2494 cases of ROP were included in this meta-analysis. Adjusted analysis showed that sepsis was closely related to any stage of ROP (OR = 1.57, 95% CI 1.31 to 1.89) and severe stage of ROP (OR = 2.33, 95% CI 1.21 to 4.51) in premature infants, with 56.3% and 81.8% heterogeneity, respectively. Subgroup analyses showed that heterogeneity was obvious in prospective cohort studies (I2= 62.1%, p<0.001). In a sensitivity analysis, we found that removing any single study did not significantly change the overall effect value. The quality of the evidence was rated as low for both any stage of ROP and severe stage of ROP.ConclusionsSepsis increases the risk of ROP in preterm infants. However, considering that all included studies are observational and causality can rarely be established, additional evidence is needed to substantiate this finding and provide advice for practice.

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Is dezocine effective and safe in preventing opioids-induced cough during general anaesthesia induction? A protocol for systematic review and meta-analysis

BMJ Open ◽

10.1136/bmjopen-2019-035691 ◽

2020 ◽

Vol 10 (6) ◽

pp. e035691

Author(s):

Li-xian He ◽

Ken Shao ◽

Jie Ma ◽

Yuan-yuan Zhao ◽

Yun-tai Yao

Keyword(s):

Systematic Review ◽

Adverse Effects ◽

Treatment Effects ◽

Meta Analysis ◽

Biomedical Literature ◽

Sensitivity Analyses ◽

Systemic Review ◽

Cochrane Library ◽

Significant Heterogeneity ◽

Anaesthesia Induction

IntroductionCough is often observed when administrating a bolus of opioids. Opioid-induced cough (OIC) is mostly transient, benign and self-limiting, but could be associated with adverse effects. Numerous pharmacological and non-pharmacological interventions have been used to manage OIC with controversial efficacy and safety. Recent studies suggested that, pretreatment of intravenous dezocine (DZC) could completely suppress OIC during anaesthesia induction. To address this knowledge lack, we will perform a systemic review and meta-analysis to evaluate the efficacy of DZC on OIC and possible complications. We provide here a protocol that will outline the methods and analyses planned for the systematic review.MethodsPubMed, Embase, Cochrane Library, Web of Science as well as Chinese BioMedical Literature & Retrieval System (SinoMed), China National Knowledge Infrastructure, Wanfang Data and VIP Data will be searched from 1978 to 31 December 2019 to identify all randomised controlled trials comparing DZC with placebo on the incidence and severity of OIC. Primary outcomes of interest include the incidence and severity of OIC. Secondary outcomes of interest include possible complications or adverse effects of DZC. Two authors will independently extract relevant variables and outcome data. For continuous variables, treatment effects will be calculated as weighted mean difference and 95% CI. For dichotomous data, treatment effects will be calculated as OR and 95% CI. Each outcome will be tested for heterogeneity, and randomised-effects or fixed-effects model will be used in the presence or absence of significant heterogeneity. Sensitivity analyses will be done by examining the influence of statistical model and individual trial(s) on estimated treatment effects. Publication bias will be explored through visual inspection of funnel plots of the outcomes. Statistical significance will be defined as p<0.05.Ethics and disseminationThis study is a protocol of meta-analysis of previously published literatures, ethical approval was not necessary according to the Ethical Committee of Fuwai Hospital. The study will be submitted to a peer-reviewed journal and disseminated via research presentations.PROSPERO registration numberCRD42019141255.

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A Systematic Review of Interventions to Increase Awareness, Knowledge, and Folic Acid Consumption before and during Pregnancy

American Journal of Health Promotion ◽

10.4278/06051566r2.1 ◽

2008 ◽

Vol 22 (4) ◽

pp. 237-245 ◽

Cited By ~ 21

Author(s):

Corina Mihaela Chivu ◽

Theodore H. Tulchinsky ◽

Karla Soares-Weiser ◽

Rony Braunstein ◽

Mayer Brezis

Keyword(s):

Systematic Review ◽

Folic Acid ◽

Data Extraction ◽

Interrupted Time Series ◽

Cochrane Library ◽

Case Control Studies ◽

Effective Interventions ◽

Before And After ◽

Quasi Experimental ◽

Time Series Studies

Objective. We conducted a systematic review of studies designed to increase awareness of, knowledge about, and consumption of folic acid before and during pregnancy. Data sources. Studies were identified from Cochrane Library, Medline, and the references of primary studies and reviews. Study inclusion and exclusion criteria. Studies included randomized controlled trials, quasi-experimental interrupted time series studies, follow-up studies, case-control studies, and before-and-after studies, all of which were conducted between 1992 and 2005 on women ages 15 to 49 years and/or health professionals, evaluating awareness and/or knowledge and/or consumption of folic acid both before and after intervention. Studies were excluded if data were not presented both before and after intervention or were other outcomes than those mentioned here. Data extraction. Data were extracted in relation to characteristics of studies, participants, interventions, and outcomes. Data synthesis. Because of heterogeneity, we performed a narrative synthesis describing the direction and the size of effects. Results. On average, women's awareness increased from 60% to 72%, knowledge from 21% to 45%, and consumption from 14% to 23%. Conclusions. Interventions had a positive effect on folic acid intakes before and during pregnancy, although the average usage reached less than 25%. So what? Further research is needed to design more effective interventions to increase periconceptional use of folic acid.

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Does Vitamin D Deficiency in Different Periods of Gestation Have the Same Effect on Preterm Birth? A Systematic Review and Meta-Analysis

10.21203/rs.3.rs-15534/v1 ◽

2020 ◽

Author(s):

bin Yi ◽

Rui-han Lian ◽

Ping-an Qi ◽

Tao Yuan ◽

Pei-jing Yan ◽

...

Keyword(s):

Systematic Review ◽

Vitamin D ◽

Preterm Birth ◽

Vitamin D Deficiency ◽

Meta Analysis ◽

Cochrane Library ◽

Second Trimester ◽

Case Control Studies ◽

Cross Sectional ◽

Vitamin D Levels

Abstract Background: Current studies suggest that vitamin D deficiency during pregnancy can produce a certain effect for preterm birth, but there is no research showing whether vitamin D deficiency has a consistent effect in different pregnancies; thus, we conducted a systematic review and meta-analysis of 24 observational studies, grouping them according to the gestational age at the time of serum sampling, to investigate whether vitamin D deficiency in different periods of gestation has different effects on preterm birth and to provide an evidence-based basis for pregnant women to measure and supplement vitamin D. Methods: The databases PubMed-Medline, EMBASE, the Cochrane Library, Web of Science, EBSCO, CBM, and CNKI were searched until July 2019. Two researchers independently assessed the eligibility and quality of studies, and STATA 12.0 software was used for meta-analysis. Result: Seven cohort studies, 13 case-control studies, and four cross-sectional studies were included from 2500 articles by inclusion and exclusion criteria. After adjusting for age, race, and other confounding factors, meta-analysis results showed that vitamin D deficiency in the first trimester, the second trimester and the third trimester did not increase the risk of preterm birth (odds ratio (OR) = 1.01, 95% confidence interval (CI) (0.88, 1.16), P = 0.867; OR = 1.12, 95%CI (0.92, 1.37), P = 0.249; OR = 1.05, 95%CI (0.87, 1.27), P = 0.602). However, there was moderate heterogeneity in the study of vitamin D deficiency in the second trimester, and subgroup analysis suggested that vitamin D deficiency in the second trimester may increase the risk of preterm birth (OR = 1.33, 95%CI (1.15, 1.54), P = 0.000). A sensitivity analysis of the second trimester showed that excluding any one study did not significantly change the results. Conclusions: Vitamin D deficiency in early and late pregnancy may not be associated with preterm birth, while vitamin D deficiency in middle pregnancy is likely to have an important effect on preterm birth. Vitamin D levels should be measured in the second trimester of pregnancy, and vitamin D supplements should be provided if necessary.

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Can Smartphone Apps Increase Physical Activity? Systematic Review and Meta-Analysis (Preprint)

10.2196/preprints.12053 ◽

2018 ◽

Author(s):

Amelia Romeo ◽

Sarah Edney ◽

Ronald Plotnikoff ◽

Rachel Curtis ◽

Jillian Ryan ◽

...

Keyword(s):

Physical Activity ◽

Systematic Review ◽

Meta Analysis ◽

Target Population ◽

Sensitivity Analyses ◽

Cochrane Library ◽

Smartphone Apps ◽

Intervention Effects ◽

Randomized Controlled ◽

Steps Per Day

BACKGROUND Smartphone apps are a promising tool for delivering accessible and appealing physical activity interventions. Given the large growth of research in this field, there are now enough studies using the “gold standard” of experimental design—the randomized controlled trial design—and employing objective measurements of physical activity, to support a meta-analysis of these scientifically rigorous studies. OBJECTIVE This systematic review and meta-analysis aimed to determine the effectiveness of smartphone apps for increasing objectively measured physical activity in adults. METHODS A total of 7 electronic databases (EMBASE, EmCare, MEDLINE, Scopus, Sport Discus, The Cochrane Library, and Web of Science) were searched from 2007 to January 2018. Following the Population, Intervention, Comparator, Outcome and Study Design format, studies were eligible if they were randomized controlled trials involving adults, used a smartphone app as the primary or sole component of the physical activity intervention, used a no- or minimal-intervention control condition, and measured objective physical activity either in the form of moderate-to-vigorous physical activity minutes or steps. Study quality was assessed using a 25-item tool based on the Consolidated Standards of Reporting Trials checklist. A meta-analysis of study effects was conducted using a random effects model approach. Sensitivity analyses were conducted to examine whether intervention effectiveness differed on the basis of intervention length, target behavior (physical activity alone vs physical activity in combination with other health behaviors), or target population (general adult population vs specific health populations). RESULTS Following removal of duplicates, a total of 6170 studies were identified from the original database searches. Of these, 9 studies, involving a total of 1740 participants, met eligibility criteria. Of these, 6 studies could be included in a meta-analysis of the effects of physical activity apps on steps per day. In comparison with the control conditions, smartphone apps produced a nonsignificant (P=.19) increase in participants’ average steps per day, with a mean difference of 476.75 steps per day (95% CI −229.57 to 1183.07) between groups. Sensitivity analyses suggested that physical activity programs with a duration of less than 3 months were more effective than apps evaluated across more than 3 months (P=.01), and that physical activity apps that targeted physical activity in isolation were more effective than apps that targeted physical activity in combination with diet (P=.04). Physical activity app effectiveness did not appear to differ on the basis of target population. CONCLUSIONS This meta-analysis provides modest evidence supporting the effectiveness of smartphone apps to increase physical activity. To date, apps have been most effective in the short term (eg, up to 3 months). Future research is needed to understand the time course of intervention effects and to investigate strategies to sustain intervention effects over time.

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