Research Article

Season of Birth and Exceptional Longevity: Comparative Study of American Centenarians, Their Siblings, and Spouses

Table 5

Odds ratios ( values) to become a centenarian as predicted by conditional logistic regression (fixed effects) for different age cut-off subgroups. Effects of month of birtha.

VariableAll siblingsSiblings survived to age 30Siblings survived to age 50Siblings survived to age 70

Month of birth:
 January1.13 (0.387)1.11 (0.472)1.11 (0.463)1.09 (0.537)
 February1.25 (0.101)1.25 (0.109)1.24 (0.124)1.16 (0.303)
 MarchReferenceReferenceReferenceReference
 April1.15 (0.320)1.15 (0.337)1.16 (0.320)1.09 (0.567)
 May1.20 (0.218)1.17 (0.288)1.19 (0.251)1.15 (0.373)
 June1.20 (0.229)1.00 (0.254)1.18 (0.284)1.11 (0.486)
 July1.03 (0.855)1.19 (0.991)1.01 (0.941)1.00 (0.990)
 August1.25 (0.110)1.24 (0.125)1.27 (0.100)1.21 (0.198)
 September1.44 (0.006) c1.43 (0.009)c1.45 (0.007) c1.39 (0.022)
 October1.43 (0.008) c1.37 (0.021) c1.37 (0.022) c1.27 (0.099)
 November1.51 (0.003) b,c1.48 (0.005) c1.47 (0.006) c1.41 (0.017)
 December1.17 (0.266)1.13 (0.380)1.17 (0.283)1.11 (0.486)

Female sex3.77 (<0.001)3.82 (<0.001)3.80 (<0.001)3.41 (<0.001)

Pseudo 0.08110.08610.08710.0766
Number of observations12,13210,3939,7248,123

aStatistically significant effects ( ) are highlighted in bold.
bStatistically significant after Bonferroni adjustment.
cStatistically significant after Benjamini-Hochberg procedure.