Introduction:
Drinking alcohol before sleeping (Ne-Zake) or in the morning (Mukae-Zake) is occasionally seen in Japan although it is well known that drinking alcohol have some negative effects on sleep. There have been studies which indicated that alcohol worsen sleep quality and quantity however few which investigated how alcohol before sleeping and no which noticed on how alcohol in the morning affects. The purpose of this study is to verify the relationship between Ne-Zake and/or Mukae-Zake and insomnia adjusting the influence of quality and frequency of drinking on the relationship.
Hypothesis:
We assessed the hypothesis that there is a significant association between Ne-Zake and/or Mukae-Zake and sleeplessness but this association can be confounded by quality and frequency of drinking.
Method:
Seven hundred and forty-six farmers who underwent annual medical checkups were analyzed. Ne-Zake was defined as “drinking as a sleeping aid” and Mukae-Zake was defined as “drinking in order to get calm down or to fix hungover”. Athene Insomnia Scale (AIS) was used to evaluate objective sleeplessness. AIS consists of 8 questions, which were evaluated from 0 (no sleeplessness) to 3 points (severe sleeplessness), asking the sleeping status in the previous 2 weeks. Insomnia was defined by AIS point more than 6. We conducted the multivariable logistic analysis, setting the presence of insomnia as a dependent variable and the presence of Ne-Zake and Mukae-Zake, quantity of alcohol at one time, frequency of drinking, sleeping related diseases (sleep apnea syndrome, restless leg syndrome, narcolepsy, limb movement disorder, depression), gender, and age as independent variables.
Results:
Among a total of 746 farmers (mean age 59.5 years; 74.1% men), insomnia, Ne-Zake, and Mukae-Zake were observed in 151 (20.2%), 140 (18.8%) and 37 (5.0%), respectively. Adjusted odds ratios (95% Confidence Intervals) of Ne-Zake and Mukae-Zake were 1.75 (1.07-2.88) and 3.01 (1.41-6.42). The association of Ne-Zake was consistent between men and women but that of Mukae-Zake was stronger in men than in women. (P-values for interaction = 0.98 and 0.03, respectively).
Conclusion:
Both Ne-Zake and Mukae-Zake had statistically positive significant association with insomnia independent of quantity and frequency of drinking. It may indicate that the timing of drinking alcohol has a stronger relationship with insomnia than quantity and frequency of drinking does. The feature of farmers’ lives in which they can decide their life style might give more opportunities to have Ne-Zake and/or Mukae-Zake than groups with well-scheduled working environment. This result can be utilized to improve farmers’ further physical and psychological health related to alcohol by encouraging to pay attention to not only the quantity or frequency of alcohol drinking but also the timing in a day.
Letter transpositions and morphemic boundaries in the second language processing of derived words: An exploratory study of individual differences
