Association between physical activity and healthcare costs by weight status in middle age: Evidence from the Northern Finland Birth Cohort 1966

Abstract

Abstract Objectives To study the association of physical activity (PA) with individual-level outpatient primary healthcare (PHC) costs in midlife according to body mass index (BMI) categories. Methods The study population comprised 4 076 participants from the Northern Finland Birth Cohort 1966. The probability of having PHC costs and the previous year PHC cost levels at age 46 according to BMI and self-reported PA and their joint interactions were estimated using a two-part model. The BMI categories were healthy weight, overweight, and obesity at ages 31 and 46, and weight gain between such ages. The PA categories were inactive and active at ages 31 and 46, and turning inactive and turning active between such ages. The adjusted predicted annual individual-level PHC costs (€) for the combined BMI and PA categories were estimated. Results The participants with obesity had a significantly higher probability of having PHC costs (OR = 3.15, 95%CI 1.23–8.02 for females; OR = 3.77, 95%CI 1.31–10.85 for males) than the participants with healthy weight. The participants with obesity (OR = 1.33, 95%CI 1.01–1.75), and those with weight gain (OR = 1.22, 95%CI 1.03–1.44) had significantly higher PHC costs than the participants with healthy weight among females, but not among males. Joint associations of any of the BMI and PA categories with the probability of having PHC costs or cost levels were not found. Among females, the inactive participants with weight gain had 25% higher predicted costs than the inactive participants with healthy weight; and among the participants who turned active, those with weight gain had 65% higher predicted costs than those with healthy weight. Among males with healthy weight, the inactive ones had 38% higher predicted costs than the active participants. Conclusions Reaching the current PA recommendations does not mitigate the impact of obesity and weight gain on outpatient PHC costs in midlife.