Physical Activity and Health
Association between steps per day and mortality in people with and without metabolic syndrome: NHANES 2005-2006 Pardis Parvizi* Pardis Parvizi Shivangi Bajpai Lingsong Kong Amanda Paluch
Background: Metabolic syndrome (MetS) is a constellation of conditions including elevated waist circumference, high blood pressure, elevated fasting glucose, high triglycerides, and low high-density lipoprotein (HDL) cholesterol. Individuals with three or more of these criteria are classified as having MetS, which increases the risk of cardiovascular disease and mortality. Physical activity, including daily step counts, may help mitigate these risks. Purpose: To examine the association between daily steps and all-cause mortality among adults aged 40 years and older with and without MetS using data from the 2005–2006 National Health and Nutrition Examination Survey (NHANES). Methods: Participants (n=1,041 without MetS; n=1,356 with MetS) aged ≥40 years with valid accelerometer-based physical activity data (≥1 valid day with ≥10 hours of wear time) were included. MetS was classified by meeting at least three of five risk factors using examination, questionnaire, and laboratory data. Daily steps were categorized as <4,000 (reference), 4,000–7,999, 8,000–11,999, and ≥12,000 steps. Mortality status was followed through 2019. Survey-weighted Cox proportional hazards models estimated hazard ratios (HR) for mortality across step ranges, adjusting for age, sex, race, BMI, smoking, and comorbidities. Results: Over 12.0±3.7 years of follow-up, 255 deaths occurred in the non-MetS group and 459 in the MetS group. There was a non-linear dose-response relationship, in which higher daily step ranges were associated with less mortality risk in both groups, until plateauing at 8,000 to 12, 000 daily steps. Adults with or without MetS who walked at least 8,000 daily steps had a 60-70% less risk of mortality, compared to adults taking <4,000 daily steps (Table 1). Conclusion: Higher daily steps are associated with lower mortality risk in both adults with and without MetS. These findings highlight the importance of physical activity for longevity across all risk groups.
