Table 5 Risk of Pontiac fever according to different factors, by gender
Risk factorsWomen (RR (95% CI) and p value) n = 581Men (RR (95% CI) and p value) n = 247Men and women (RR (95% CI) and p value) n = 828
Age (<75 years; 75–90; >90 years)(p = 0.91)(p = 0.54)(p = 1)
    75–90 vs <75 years0.94 (0.31 to 2.82) (p = 1)1.34 (0.25 to 7.14) (p = 1)1.12 (0.45 to 2.80) (p = 1)
    >90 years vs <75 years0.72 (0.19 to 2.82) (p = 0.72)2.55 (0.38 to 17.30) (p = 0.32)1.09 (0.36 to 3.30) (p = 1)
Sex (women/men)1.12 (0.50 to 2.49) (p = 1)
Number of showers (median cut-off point)0.79 (0.32 to 1.96) (p = 0.64)3.89 (0.46 to 32.71) (p = 0.23)1.08 (0.49 to 2.38) (p = 1)
Immunosuppressive therapy4.97 (1.30 to 19.00) (p = 0.07)11.62 (2.00 to 67.47) (p = 0.09)6.24 (2.12 to 18.38) (p = 0.01)
Smoking habits (never; past; current)(p = 1)(p = 0.74)(p = 0.81)
    Past vs never1.05 (0.25 to 4.41) (p = 1)0.47 (0.06 to 3.81) (p = 0.70)0.75 (0.23 to 2.44) (p = 0.79)
    Current vs never1.07 (0.15 to 7.73) (p = 1)1.11 (0.14 to 8.81) (p = 1)1.09 (0.27 to 4.50) (p = 0.71)
Alcoholism0.65 (0.04 to 10.42) (p = 1)1.54 (0.20 to 11.91) (p = 0.51)0.70 (0.10 to 5.04) (p = 1)
Diabetes1.23 (0.43 to 3.59) (p = 0.76)0.74 (0.09 to 5.85) (p = 1)1.09 (0.42 to 2.80) (p = 0.8)
Cancer/haemopathy0.52 (0.07 to 3.79) (p = 1)1.21 (0.16 to 9.48) (p = 0.59)0.72 (0.18 to 2.98) (p = 1)
History of respiratory conditions2.47 (0.99 to 6.18) (p = 0.1)0.28 (0.02 to 4.79) (p = 0.36)1.50 (0.62 to 3.60) (p = 0.42)
History of cardiovascular conditions1.14 (0.27 to 4.76) (p = 0.69)0.99 (0.06 to 16.25) (p = 1)0.92 (0.22 to 3.76) (p = 1)
History of cognitive conditions*0.47 (0.14 to 1.56) (p = 0.31)0.39 (0.05 to 3.12) (p = 0.69)0.44 (0.16 to 1.26) (p = 0.14)
Other comorbidities0.93 (0.38 to 2.27) (p = 1)0.28 (0.04 to 2.26) (p = 0.27)0.72 (0.32 to 1.61) (p = 0.55)
  • *Dementia, mental retardation and Parkinson’s disease.