The influence of partner's behavior on health behavior change: the English Longitudinal Study of Ageing.

IMPORTANCE Couples are highly concordant for unhealthy behaviors, and a change in one partner's health behavior is often associated with a change in the other partner's behavior. However, no studies have explicitly compared the influence of having a partner who takes up healthy behavior (eg, quits smoking) with one whose behavior is consistently healthy (eg, never smokes). OBJECTIVE To examine the influence of partner's behavior on making positive health behavior changes. DESIGN, SETTING, AND PARTICIPANTS We used prospective data from married and cohabiting couples (n, 3722) participating in the English Longitudinal Study of Ageing, a large population-based cohort of older adults (≥50 years). Studying men and women who had unhealthy behaviors in 3 domains at baseline (ie, smoking, physically inactive, or overweight/obese), we used logistic regression analysis to examine the influence of the partner's behavior in the same domain on the odds of positive health behavior change over time. MAIN OUTCOMES AND MEASURES Smoking cessation, increased physical activity, and 5% weight loss or greater. RESULTS Across all domains, we found that when one partner changed to a healthier behavior (newly healthy), the other partner was more likely to make a positive health behavior change than if their partner remained unhealthy (smoking: men 48% vs 8%, adjusted odds ratio [OR], 11.82 [95% CI, 4.84-28.90]; women 50% vs 8%, OR, 11.23 [4.58-27.52]) (physical activity: men 67% vs 26%, OR, 5.28 [3.70-7.54]; women 66% vs 24%, OR, 5.36 [3.74-7.68]) (weight loss: men 26% vs 10%, OR, 3.05 [1.96-4.74]; women 36% vs 15%, OR, 3.08 [1.98-4.80]). For smoking and physical activity, having a consistently healthy partner also predicted positive change, but for each domain, the odds were significantly higher in individuals with a newly healthy partner than those with a consistently healthy partner (smoking: men OR, 3.08 [1.43-6.62]; women OR, 5.45 [2.44-12.16]) (physical activity: men OR, 1.92 [1.37-2.70]; women OR, 1.84 [1.33-2.53]) (weight loss: men OR, 2.28 [1.36-3.84]; women OR, 2.86 [1.55-5.26]). CONCLUSIONS AND RELEVANCE Men and women are more likely to make a positive health behavior change if their partner does too, and with a stronger effect than if the partner had been consistently healthy in that domain. Involving partners in behavior change interventions may therefore help improve outcomes.