Impactos da dor lombar em adultos de meia idade e idosos - Resultados do Baltimore Longitudinal Study of Aging

Abstract

Low back pain (LBP) is a global and urgent public health concern due to its high prevalence, economic repercussions and other health aspects. The aim of this thesis is to produce two manuscripts: (1) association of presence and intensity of LBP in the previous year and physical function (PF) and health-related quality of life (HRQoL); (2) association between the presence and intensity of previous and current LBP and daily physical activity (PA), sedentary behavior, activity fragmentation and meeting PA guidelines in middle- and older- aged adults. This is a cross-sectional analysis with volunteers from the Baltimore Longitudinal Study of Aging, over 40 years old, who answered questions about presence and intensity of LBP in the previous year. For the first manuscript, participants self-reported PF and HRQoL (SF-12) and performed objective PF tests ([Short Physical Performance Battery Expanded - ExSPPB] including usual gait speed, Narrow walk, chair stands, standing balance), endurance performance (long distance corridor walk) and fatigability. For the second manuscript, volunteers wore Actiheart accelerometers for thr subsequent week. Generalized linear models and logistic regression models were generated crude and adjusted. In manuscript 1, 1,500 volunteers participated (52.5% women, 70.3% white) aged 69.0 (+13.1). 642 (42.8%) reported LBP with mean intensity of 4.1 (+2.2). After adjustments, presence of LBP was associated with self-reported PF (OR 1.73, 95% CI 1.27 to 2.37), physical domain of HRQOL (β -0.03, 95% CI -0.04 to -0 .02) and poorer chair stand performance (β -0.05, 95% CI -0.09 to -0.008). Higher LBP intensity was associated with lower HRQoL – physical domain (β -0.01, 95% CI -0.02 to -0.007), poorer ExSPPB performance (β -0.01, 95% CI -0.02 to -0.004), slower usual gait speed (β -0.01, 95% CI -0.02 to -0.004), lower total standing balance time (β -0.01, 95% CI -0.02 to - 0.001) and higher fatigability (OR 1.13, 95% CI 1.01 to 1.25). In manuscript 2, 662 volunteers (50.8% women, 68.1% white) aged 68.0 (+11.4) Years were included. 240 (36.3%) reported previous LBP (<12 weeks) with mean pain intensity of 3.5(+2.0), and 38 (5.7%) current LBP with mean pain intensity of 4.1 (+2 .3). Participants reporting current LBP had lower levels of objectively measured total (β -0.18, 95% CI -0.34 to -0.02) and vigorous PA (β -0.29, 95% CI -0.56 to -0.007) and lower odds to meet PA guidelines (OR 0.20, 95% CI 0.05 to 0.92) regardless of pain intensity. Previous LBP was not associated with PA outcomes. We conclude that presence of LBP was more consistently associated with self-reported PF, whereas higher LBP intensity were associated with objectively measured PF and high fatigability. Regardless of intensity, presence of current LBP seems to negatively interfere in PA levels, making difficult to meet PA guidelines recommendation. The decrease in total PA levels seem to be driven by a decrease in vigorous PA, with no impact on light and moderate PA, sedentary behavior and activity fragmentation.