Complementary medicine use and flu vaccination - A nationally representative survey of US adults

Background: Prior research presented inconsistent results with less, equal or higher vaccination rates among patients using complementary medicine. Given that complementary medicine includes a wide range of therapies, variable vaccination patterns may occur within consultations with different professions. This analysis aims to to evaluate differences between categories of complementary medicine regarding vaccination behavior among US adults.

Methods and results: This analysis used data from the 2017 National Health Interview Survey (NHIS; n = 26,742; response rate 80.7%). Prevalences of flu vaccination, consultations with complementary medicine practitioners in the past 12 months and their potential interactions were examined. 42.7% of participants had received flu vaccination in the past 12 months, 32.4% had seen one or more complementary medicine practitioner. Users of any type of complementary medicine were as likely as non-users to have received a flu vaccination (44.8% users versus 41.7% non-users; p = 0,862; adjusted odds ratio [AOR] = 1.01, 95% confidence interval [CI] = 0.95-1.07). Regarding specific complementary medicine types, individuals consulting with naturopaths (p < 0.001; AOR = 0.67, 95 %CI = 0.54-0.82), homeopaths (p < 0.001; AOR = 0.55; 95 %CI = 0.44-0.69) and chiropractors (p = 0.016; AOR = 0.9, 95 %CI = 0.83-0.98) were less likely, while other complementary medicine approaches showed no significant association with flu vaccination behavior. Independent predictors for a flu shot were prior diabetes, cancer, current asthma, kidney disease, overweight and current pregnancy. As well, higher educational level, age, ethnicity, health insurance coverage and having seen a general physician or medical specialist in the past 12 months were also associated with a higher vaccination rate.

Conclusions: Complementary medicine users were equally likely to receive an influenza vaccination compared with non-users. Different complementary therapies showed varied associations with vaccination behavior. Further analyses may be needed to distinguish influencing factors among patients' vaccination behavior.