Seasonality patterns of mood and behavior in the Old Order Amish

Although humans have become partially isolated from physical seasonal environmental changes through artificial lighting and temperature control, seasonal changes in mood and behavior have been described across hemispheres, continents, ethnicities and occupations. The Old Order Amish are more exposed than the general population to environmental seasonal changes both occupationally as well as through their limited use of electric light in the winter and air conditioning in the summer; yet, their seasonal changes in mood and behavior have not been previously studied.

The aim of this study was to analyze seasonal patterns in mood and behavior in the Old Order Amish of Lancaster County, Pennsylvania, who returned completed Seasonal Pattern Assessment Questionnaires (SPAQ). Monthly seasonal patterns were analyzed with repeated measures ANOVAs, followed by a post hoc t-test if significant. The χ² was used for presence or absence of seasonal patterns for each item.

More than 75% of the participants reported at least one seasonal change. More than 75 % endorsed seasonality in "feeling best" but only <25% did so for "feeling worst". Mood-wise, the best month was May, and the worst months were January and February.

There were significant seasonal patterns for all mood and behavior items reported by the majority of participants. The results were consistent with an overall winter pattern of seasonality previously consistently reported in predominantly Caucasian populations.