Daily variations in ambulance calls for selected causes in Arkhangelsk, Russia: potential role of excessive alcohol consumption on weekends

OBJECTIVE To assess daily variations in ambulance calls for cardiovascular diseases (CVDs), mental and behavioral disorders, and external causes in Arkhangelsk, Northwest Russia, in 2000-2008. STUDY DESIGN A population-based study. METHODS Data about all ambulance calls during the years 2000-2008 were obtained from the Arkhangelsk ambulance station. Information about patient's gender, age, doctor's diagnosis according to International Classification of Diseases, 10th revision, and the date of call were recorded. Pearson's Chi-squared tests were used for comparing proportions of ambulance calls across the week for CVDs (I00-99), mental and behavioral disorders (F00-F99), and external causes (S00-T98, V01-Y98). The ratio of incidence of ambulance calls on Saturday, Sunday, and Monday versus the rest of week was also calculated. RESULTS There is a significant daily variation (p < 0.001) in calls for CVDs in men and women aged 18-59 and women aged 60 years and older, with increased numbers of calls on weekends and Mondays varying between 2 and 3% excess calls. For mental and behavioral disorders, a similar pattern was found in the age group of 18-59 year-olds. Ratios for the number of calls during weekends and Mondays vs. the rest of the week were 1.05 (95% CI: 1.02-1.08) among women and 1.02 (95% CI: 1.00-1.05) among men. For external causes, a significant variation and an increase in ambulance calls during Saturdays, Sundays, and Mondays from 4 to 17% excess calls was observed for both age and gender groups. CONCLUSIONS The observed daily variations in ambulance calls with an increased number of calls on weekends and Mondays for CVDs, mental and behavioral disorders, and external causes may be associated with excessive alcohol consumption on the weekends. Further research using data on individual levels of alcohol consumption are warranted.