Estimating Lactase Nonpersistence Distributions in the Multi-Ethnic Canadian Demographic: A Population-Based Study

Abstract Objectives The lactase persistence/nonpersistence (LP/LNP) phenotypes follow a geographic pattern that is rooted in the gene-culture coevolution observed throughout the history of human migrations. The immense size and relatively open immigration policy have drawn migrants of diverse ethnicities to Canada. Among the multicultural demographic, two-thirds of the population are derived from the British Isles and northwestern France. A recent assessment of worldwide lactase distributions found Canada to have an LNP rate of 59% (confidence interval [CI] 44%–74%). This estimate is rather high compared with earlier reports that listed Canada as a country with a 10% LNP rate; the authors had also noted that biases were likely because their calculations were based largely on Aboriginal studies. We hereby present an alternate LNP prevalence estimate at the national, provincial and territorial level. Methods We applied the referenced LNP frequency distribution data to the 2016 population census to account for the current multi-ethnic distributions in Canada. Prevalence rates for Canada, the provinces and territories were calculated. Results The national LNP rate is estimated at 44% (CI 41%–47%) after accounting for the 254 ethnic groups, with the lowest rates found in the eastern provinces and the highest rates in the Northwest Territories (57%) and Nunavut (66%), respectively. Conclusion Despite the heterogeneous nature of the referenced data and the inference measures taken, evidently, the validity of our LNP estimate is anchored on the inclusion of multi-ethnic groups representing the current Canadian demographic.

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Lymphoproliferative malignancies in patients with neurofibromatosis 1

Orphanet Journal of Rare Diseases ◽

10.1186/s13023-021-01856-8 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Christina Bergqvist ◽

François Hemery ◽

Arnaud Jannic ◽

Salah Ferkal ◽

Pierre Wolkenstein

Keyword(s):

General Population ◽

Medical History ◽

Hodgkin Lymphoma ◽

Incidence Rate ◽

Population Based ◽

Neurofibromatosis 1 ◽

Population Based Study ◽

Non Hodgkin Lymphoma ◽

History Of

AbstractNeurofibromatosis 1 (NF1) is an inherited, autosomal-dominant, tumor predisposition syndrome with a birth incidence as high as 1:2000. A patient with NF1 is four to five times more likely to develop a malignancy as compared to the general population. The number of epidemiologic studies on lymphoproliferative malignancies in patients with NF1 is limited. The aim of this study was to determine the incidence rate of lymphoproliferative malignancies (lymphoma and leukemia) in NF1 patients followed in our referral center for neurofibromatoses. We used the Informatics for Integrated Biology and the Bedside (i2b2) platform to extract information from the hospital’s electronic health records. We performed a keyword search on clinical notes generated between Jan/01/2014 and May/11/2020 for patients aged 18 years or older. A total of 1507 patients with confirmed NF1 patients aged 18 years and above were identified (mean age 39.2 years; 57% women). The total number of person-years in follow-up was 57,736 (men, 24,327 years; women, 33,409 years). Mean length of follow-up was 38.3 years (median, 36 years). A total of 13 patients had a medical history of either lymphoma or leukemia, yielding an overall incidence rate of 22.5 per 100,000 (0.000225, 95% confidence interval (CI) 0.000223–0.000227). This incidence is similar to that of the general population in France (standardized incidence ratio 1.07, 95% CI 0.60–1.79). Four patients had a medical history leukemia and 9 patients had a medical history of lymphoma of which 7 had non-Hodgkin lymphoma, and 2 had Hodgkin lymphoma. Our results show that adults with NF1 do not have an increased tendency to develop lymphoproliferative malignancies, in contrast to the general increased risk of malignancy. While our results are consistent with the recent population-based study in Finland, they are in contrast with the larger population-based study in England whereby NF1 individuals were found to be 3 times more likely to develop both non-Hodgkin lymphoma and lymphocytic leukemia. Large-scale epidemiological studies based on nationwide data sets are thus needed to confirm our findings.

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The association between subclinical hypothyroidism and TPOAb positivity with infertility in a population-based study: Tehran thyroid study (TTS)

BMC Endocrine Disorders ◽

10.1186/s12902-021-00773-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Batul Birjandi ◽

Fahimeh Ramezani Tehrani ◽

Atieh Amouzegar ◽

Maryam Tohidi ◽

Razieh Bidhendi Yarandi ◽

...

Keyword(s):

Thyroid Autoimmunity ◽

Population Based ◽

Cross Sectional Study ◽

Cross Sectional ◽

Population Based Study ◽

History Of ◽

Autoimmune Condition ◽

Biochemical Measurements ◽

Adverse Pregnancy ◽

Adjusted Logistic Regression

Abstract Background Thyroid autoimmunity(TAI) is the most prevalent autoimmune condition in women of fertile age. There are increasing data regarding the association of thyroid dysfunction and thyroid autoimmunity with adverse pregnancy outcomes but there is no consensus regarding infertility and TPOAb positivity; thus we aimed to evaluate the association between thyroid TPOAb positivity and infertility in females and males in a population-based study (TTS). Methods Cross-sectional study of 3197 female and male participants in Tehran Thyroid Study (TTS) at the framework of the Tehran Lipid and Glucose Study (TLGS). Data included biochemical measurements and a self-administered questionnaire. Results A total of 12,823 cases in phase 4, 3719 cases (2108 female and 1611 male) were analyzed. The mean TSH of the infertile female and male was 2.52 ± 2.68 μIU/ml and 3.24 ± 10.26 μIU/ml respectively. The TPO median(IQR) of women with and without a history of infertility were 6.05 (3.30–13.96)and 6.04 (3.17–11.15);(P = 0.613), they were 5.08 (3.20–125.68) and 5.31 (3.93–125.68);(P = 0.490) in male participants, respectively. Results of crude and adjusted logistic regression analysis of the development of infertility by thyroid function and TPOAb, except for fT4 in male subjects, depicted no association between infertility and other variables in both crude and adjusted models. Conclusion Based on the result, thyroid autoimmunity was not associated with infertility in both females and males.

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Natural History of Functional Gastrointestinal Disorders: A 12-year Longitudinal Population-Based Study

Gastroenterology ◽

10.1053/j.gastro.2007.06.010 ◽

2007 ◽

Vol 133 (3) ◽

pp. 799-807.e1 ◽

Cited By ~ 186

Author(s):

Smita L.S. Halder ◽

G. Richard Locke ◽

Cathy D. Schleck ◽

Alan R. Zinsmeister ◽

L. Joseph Melton ◽

...

Keyword(s):

Natural History ◽

Functional Gastrointestinal Disorders ◽

Population Based ◽

Gastrointestinal Disorders ◽

Population Based Study ◽

History Of

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Parental History of Diabetes in a Population-Based Study

Diabetes Care ◽

10.2337/diacare.19.8.827 ◽

1996 ◽

Vol 19 (8) ◽

pp. 827-830 ◽

Cited By ~ 64

Author(s):

B. E. K. Klein ◽

R. Klein ◽

S. E. Moss ◽

K. J. Cruickshanks

Keyword(s):

Population Based ◽

Parental History ◽

Population Based Study ◽

History Of ◽

Parental History Of Diabetes

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Natural History of Functional Dyspepsia: A 10-Year Population-Based Study

Digestion ◽

10.1159/000243783 ◽

2010 ◽

Vol 81 (1) ◽

pp. 53-61 ◽

Cited By ~ 32

Author(s):

Linda Bjork Olafsdottir ◽

Hallgrímur Gudjonsson ◽

Heidur Hrund Jonsdottir ◽

Bjarni Thjodleifsson

Keyword(s):

Natural History ◽

Functional Dyspepsia ◽

Population Based ◽

Population Based Study ◽

History Of

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Family history of breast or ovarian cancer modifies the risk of secondary leukemia after breast cancer: Results from a population-based study

Breast Diseases A Year Book Quarterly ◽

10.1016/s1043-321x(08)79095-7 ◽

2008 ◽

Vol 19 (3) ◽

pp. 244-245

Author(s):

D.L. Hershman

Keyword(s):

Breast Cancer ◽

Ovarian Cancer ◽

Family History ◽

Population Based ◽

Secondary Leukemia ◽

Population Based Study ◽

History Of

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Abstract WMP102: Prevalence and Natural History of Superficial Siderosis: A Population-based Study

Stroke ◽

10.1161/str.48.suppl_1.wmp102 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Michael Pichler ◽

Kelly Flemming ◽

Alejandro Rabinstein ◽

Robert Brown ◽

Kejal Kantarci ◽

...

Keyword(s):

Population Based ◽

Superficial Siderosis ◽

Mri Findings ◽

Population Based Study ◽

Mri Scans ◽

History Of ◽

Lobar Hemorrhage ◽

General Elderly Population ◽

Cortical Superficial Siderosis

Introduction: Cortical superficial siderosis (cSS) refers to deposition of blood breakdown products along the cerebral cortex, causing characteristic staining patterns seen with iron-sensitive MRI techniques. Cortical superficial siderosis is a relatively rare disorder, but has been linked to cerebral amyloid angiopathy and Alzheimer’s disease. The objective of this study was to determine the frequency and natural history of cSS in the general elderly population. Methods: MRI scans from the Mayo Clinic Study of Aging (MCSA), an ongoing population-based study of elderly residents in Olmsted County, Minnesota, were reviewed by neuroradiologists. Participants with cSS were identified based on linear pattern of hypointensity on gradient recalled echo imaging consistent with cSS. Exclusion criteria were: 1) MRI findings not consistent with cSS or 2) alternative explanation for MRI findings (such as aneurysmal subarachnoid hemorrhage, intracranial surgery, or trauma). Additional data abstracted included extent of cSS, presence of cerebral microbleeds, and clinical outcome. Results: Eleven out of 1,441 participants had MRI scans showing cSS (0.8%). When stratified by age, the frequency was 0.4% in those 50 to 70 years old and 1.1% in those over 70 years old. Six participants had only focal involvement of cSS (restricted to three or fewer sulci) and five had disseminated involvement (affecting more than three sulci). Microbleeds were seen in four of five (80%) participants with disseminated cSS, but none with focal cSS. Five participants (2 focal, 3 disseminated cSS) had follow up MRI scans, with an average follow up of 25 months. There was no further hemorrhage in those with focal cSS. However, all three participants with disseminated cSS experienced additional hemorrhage: one with new microbleeds, one with new microbleeds and lobar hemorrhage, and one with sulcal subarachnoid hemorrhage and lobar hemorrhage. Conclusion: Although rare, cSS may be encountered in the general elderly population. Extent of involvement of cSS and concomitant microbleeds may be important risk factors for progression of disease and intracerebral hemorrhage. The clinical significance of focal cSS occurring in the absence of microbleeds requires further investigation.

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