As expected, the power of its prediction was somewhat greater when the measurement was made in the winter season than when it was made during the summer months, suggesting that the winter nadir [5] may be a more relevant predictive index than the summer maximum. Plasma PTH exhibited no significant predictive power in the present study, possibly because relatively few measurements were available for this index. Plasma phosphorus was significantly correlated with hand grip strength and with physical activity score in men, but only Linsitinib price with smoking habit in women. In men, it was also a robust predictor of mortality,

being ‘deleterious’, i.e. higher levels predicting greater risk. As noted above, an association between relatively high serum phosphorus levels and increased morbidity or mortality has been reported previously in other populations [7–9] and is frequently attributed to an association between raised serum phosphorus and either impaired kidney function

(due, for instance, to vascular calcification) or chronic inflammatory processes in older people. Adjustment for either plasma creatinine (kidney function index) or for plasma α1-antichymotrypsin (inflammation index) did indeed reduce the significance of the plasma phosphorus prediction. It is intriguing, but difficult to explain, that in the present study, the predictive power of plasma phosphorus was confined to the men, being essentially absent from the women (Tables 2 and 4). Another intriguing,

but unexplained, sex difference was that mortality prediction IWR-1 mouse from grip strength was essentially confined to the male subjects (Table 3) and, moreover, that hand grip strength Sclareol was correlated with several of the plasma status indices in the men, but not in the women (Table 2). Possibly, men who retain robust grip strength into old age are generally healthier than those who do not, whereas grip strength may be less predictive of good health in older women. Although previous studies on this are not conclusive [30], there appears to be some evidence for stronger mortality prediction by grip strength in older men than older women [31, 32]. Dietary and supplemental intakes As noted previously [2–4], dietary energy intake (especially when converted to a z-score) was a significant predictor of mortality in men, higher intakes being associated with lower mortality risk. This might be explained by lower mortality risk in those with relatively better appetites and higher energy expenditures (see above). Dietary calcium intakes added little or nothing to the mortality prediction by energy intakes; however, dietary phosphorus intakes were predictive in women only and were not greatly attenuated by the addition of dietary energy to the model.