Table 2.
Incidence of Non-purulent Lower Extremity Cellulitis (NLEC) in Olmsted County, Minnesota (2013) by Age, Sex, and Seasonal Periods
| Females | Males | Both Sexes | |
|---|---|---|---|
| Unadjusted Incidence | |||
| Age | Number of cases (incidence rate, per 100,000 persons) | ||
| 18–39 | 18 (71.3) | 21 (95.3) | 39 (82.5) |
| 40–49 | 6 (63.1) | 12 (135.0) | 18 (97.8) |
| 50–59 | 19 (164.5) | 19 (184.2) | 38 (173.8) |
| 60–69 | 10 (133.3) | 30 (458.4) | 40 (284.7) |
| 70–79 | 12 (265.5) | 13 (343.2) | 25 (300.9) |
| 80–99 | 17 (487.4) | 18 (802.1) | 35 (610.6) |
| All Ages | 82(132.6) | 113 (210.0) | 195 (168.6) |
| Adjusted Incidence | |||
| Season | Incidence rate (95% CI), per 100,000 persons | ||
| Warm Months† | 193.8 (139.5, 248.1) | 260.3 (189.9, 330.7) | 224.6 (180.9, 268.4) |
| Cold Months‡ | 90.1 (58.5, 121.7) | 201.1 (149.0, 253.1) | 142.3 (112.8, 171.9) |
| Overall | 133.3 (104.1, 162.5) | 225.8 (183.5, 268.0) | 176.6 (151.5, 201.7) |
Note: Unadjusted incidence is presented as number of NLEC cases along with the crude incidence rate for all age-sex groups, while adjusted incidence rates computed by season or overall are accompanied with 95% confidence intervals and are age- and sex-standardized (or age-standardized for sex-specific incidence) to the US white population in 2010. Multivariable Poisson regression analysis revealed independent effects of age, sex and season on rates of incidence, with older age (P<.001), male sex (P<.001) and “warm” season (P=.001) each associated with higher incidence of NLEC.
Pre-specified interval of May–September was used to represent warm seasonal months
Remaining months of January–April and October–December were considered to be cold seasonal months