Fig. 1
From: Seasonal variation in nocturnal home blood pressure fall: the Nagahama study
Seasonal effects on nocturnal BP changes. a The mean SBP in the morning, evening, and during sleeping by month are shown. BP monitoring at home was performed from June to February. The dotted lines are quadratic regression lines (morning SBP, p = 0.027; evening SBP, p = 0.027; sleep SBP, p < 0.001). b The percentage decline in sleep SBP [(sleep SBP−awake SBP) × 100/awake SBP] and mean temperature at Nagahama city during investigation (2013–2015) obtained from a database of the Japan Meteorological Agency are shown. The number of subjects in each subgroup is shown in columns. c Frequency differences in nocturnal dipping patterns; extreme-dipper, nocturnal SBP change ≤−20%; dipper, >−20% to ≤−10%; non-dipper, >−10%; and riser, increase in sleeping SBP compared with awakening SBP
