Association between objectively measured physical activity and gait patterns in people with Parkinson's disease: Results from a 3-month monitoring

Background. Although physical activity (PA) is known to be beneficial in improving motor symptoms of people with Parkinson's disease (pwPD), little is known about the relationship between gait patterns and features of PA performed during daily life. Objective. To verify the existence of possible relationships between spatiotemporal and kinematic parameters of gait and amount/intensity of PA, both instrumentally assessed. Methods. Eighteen individuals affected by PD (10F and 8M, age 68.0 ± 10.8 years, 1.5 ≤ Hoehn and Yahr (H&Y) < 3) were required to wear a triaxial accelerometer 24 h/day for 3 consecutive months. They also underwent a 3D computerized gait analysis at the beginning and end of the PA assessment period. The number of daily steps and PA intensity were calculated on the whole day, and the period from 6:00 to 24:00 was grouped into 3 time slots, using 3 different cut-point sets previously validated in the case of both pwPD and healthy older adults. 3D gait analysis provided spatiotemporal and kinematic parameters of gait, including summary indexes of quality (Gait Profile Score (GPS) and Gait Variable Score (GVS)). Results. The analysis of hourly trends of PA revealed the existence of two peaks located in the morning (approximately at 10) and in the early evening (between 18 and 19). However, during the morning time slot (06:00-12:00), pwPD performed significantly higher amounts of steps (4313 vs. 3437 in the 12:00-18:00 time slot, p < 0.001, and vs. 2889 in the 18: 00-24:00 time slot, p 0.021) and of moderate-to-vigorous PA (43.2% vs. 36.3% in the 12:00-18:00 time slot, p 0.002, and vs. 31.4% in the 18:00-24:00 time slot, p 0.049). The correlation analysis shows that several PA intensity parameters are significantly associated with swing-phase duration (rho −0.675 for sedentary intensity, rho 0.717 for moderate-to-vigorous intensity, p < 0.001), cadence (rho 0.509 for sedentary intensity, rho −0.575 for moderate-to-vigorous intensity, p < 0.05), and overall gait pattern quality as expressed by GPS (rho −0.498 to −0.606 for moderate intensity, p < 0.05) and GVS of knee flexion-extension (rho −0.536 for moderate intensity, p < 0.05). Conclusions. Long-term monitoring of PA integrated by the quantitative assessment of spatiotemporal and kinematic parameters of gait may represent a useful tool in supporting a better-targeted prescription of PA and rehabilitative treatments in pwPD.