Seasonal Changes in the Activity of Serum Alkaline Phosphatase

Abstract

This paper reports a seasonal variation in alkaline phosphatase (ALP) levels in the serum, with low values occurring in summer and high in winter. These variations were found both in indoor and outdoor workers and in a group of elderly women in a long-stay ward. The seasonal change in ALP was in the opposite direction to the seasonal change in the serum levels of 25-hydroxyvitamin D. No such change was seen in the serum levels of gamma- glutamyltransferase. It is suggested that the seasonal change in plasma ALP could be due to changes in the bone isoenzyme. Serum levels of calcium remained unchanged; the change in ALP may reflect a homeostatic mechanism controlling plasma calcium, which compensates for seasonal variations in vitamin D supply.

Vitamin D levels and deficiency with different occupations: a systematic review

“…Craft, equipment, machine operating, and assembling workers2812South Korea (33° - 38°N)Cross-sectional<50 nmol/L: 61.6%2. Skilled agricultural, forestry, and fishery workers2572<50 nmol/L: 38.5%Bacchel (2015) [27]Farmers6North-West Punjab, India (31°15′N)Cross-sectional<75 nmol/L: 50%<25 nmol/L: 50%Indoor WorkersDevgun (1981) [85]Laboratory staff8Dundee, Scotland (56°30′N)Descriptive43.9 ± 17.0Devgun (1981) [25]Indoor workers9Scotland (56°30′N)Descriptive42.9 ± 15.3Maeda (2007) [108]Plant and office workers28Sao Paulo, Brazil (23° 34′S)Descriptive94.0 ± 32.6Gulvady (2007) [109]Senior executives75Mumbai, India (19°08′ N)Descriptive<50 nmol/L: 83%Islam (2008) [110]Garment factory workers200Dhaka, Bangledesh (23°81′N)Descriptive36.7 ± 11.2<50 nmol/L: 86.5%Azizi (2009) [104]Industry, civil service, etc.104Israel, Beer Sheva (31°25′ N)Interventional57.5 ± 20.8Itoh (2011) [28]Indoor daytime workers4Kawasaki City, Japan (35°53′N)Interrupted time series49.7 ± 7.9Vu (2011) [111]Office workers213Brisbane, Australia (27°S)Descriptive62.2 ± 22.5<75 nmol/L: 43.3%<50 nmol/L: 42.5%Choi (2011) [106]1. Administration, clerical work1047Cross-sectional45.8 ± 16.5<75 nmol/L: 93.4%<50 nmol/L: 87.1%53.8 ± 18.5<75 nmol/L: 87.1%<50 nmol/L: 50%2.…”

“…Serum 25-(OH)D levels vary widely according to the season of the year in which the studies or collection of samples are conducted [25, 85], thus establishing season of the year as a confounder of serum vitamin D level [84]. Several lines of evidence suggest that there is a high variability in seasonal vitamin D levels across the globe [86, 87].…”

“…An Indonesian study likewise showed that vitamin D deficiency may occur in women with indoor occupations [24]. In contrast, other evidence confirms that outdoor workers have comparatively high serum vitamin D levels [25–27]. However, the association between occupational factors (e.g.…”

Calcium‐vitamin D‐fortified milk is as effective on circulating bone biomarkers as fortified juice and supplement but has less acceptance: a randomised controlled school‐based trial

“…A significant increase in the serum BAP concentration in all groups was most likely a result of winter elevation of enzyme secretion. Seasonal variation of alkaline phosphatase activity has been reported previously (Devgun et al ., ; Douglas et al ., ). It should be noted that BAP mass concentration (not activity) was measured in the present study.…”

Preanalytical Variability of Biochemical Markers of Bone Turnover

“…Osteocalcin may be elevated in the winter and spring and total and bone alkaline phosphatase may be decreased in the winter and spring [185,186]. However, other studies, including a large cross-sectional study of subjects aged 50±80 years, has shown that the rhythms of osteocalcin and bone alkaline phosphatase coincide [63,187]. The differences between the ®ndings of these studies may be due some of them being longitudinal and the others being crosssectional.…”