Demographic characteristics of the participants
Table 1 presents the demographic characteristics and other potential confounders of all participants by sinusitis status. Among the 466 participants with sinus infection, 63.46% were females, 76.54% were non-Hispanic white, more than two-thirds had at least a college degree, 37.05% had a household income of $75,000/y or greater, 45.81% were obesity, 65.48% had allergies, and 62.63% had central obesity. Among the 2,644 participants without sinus infection, 47.49% were females, 59.09% had a college degree or above, 33.23% were obesity, 36.34% had allergies, and 48.87% had central obesity. Compared to the non-sinusitis group with lower values of BMI (28.35 ± 0.26 kg/m²), WC (96.88 ± 0.71 cm) and HPF (23.78 ± 0.02%), the group with sinusitis exhibited higher values of BMI (30.46 ± 0.62 kg/m²), WC (100.73 ± 1.53 cm) and HPF (23.94 ± 0.05%).
Table 1
Characteristics of participants in NHANES 2005–2006
| Sinusitis N = 466 | Non-sinusitis N = 2737 | P |
Age, years ± SE | 44.61 ± 0.62 | 42.51 ± 0.53 | 0.024 |
Female (%) | 293 (63.46) | 1265 (47.49) | < 0.001 |
Race | | | 0.004 |
Mexican American | 60(4.56) | 613(8.66) | |
Non-Hispanic white | 253(76.54) | 1247(70.85) | |
Non-Hispanic black | 117(10.16) | 672(11.50) | |
Others | 36(8.74) | 205(8.99) | |
Educational level | | | < 0.001 |
Less than high school | 76(9.72) | 704(16.16) | |
High school graduate | 95(21.28) | 648(24.72) | |
Some colleges or more | 295(68.99) | 1384(59.09) | |
Refuse/unsure | 0(0) | 1(0.04) | |
Income, $ | | | 0.634 |
< 20,000 | 78(12.05) | 488(12.13) | |
20,000–44,999 | 125(22.77) | 806(25.28) | |
45,000–74,999 | 108(26.06) | 653(26.69) | |
≥ 75,000 | 142(37.05) | 697(33.34) | |
Refuse/unsure | 13(2.07) | 93(2.55) | |
Anthropometric measures | | | |
Body mass index, kg/m² | 30.46 ± 0.62 | 28.35 ± 0.26 | 0.001 |
Waist circumference, cm | 100.73 ± 1.53 | 96.88 ± 0.71 | 0.008 |
Head percent fat | 23.94 ± 0.05 | 23.78 ± 0.02 | 0.008 |
Body mass index categories | | | 0.009 |
Normal weight | 116(27.48) | 832 (33.63) | |
Overweight | 129(26.71) | 942(33.1) | |
Obese | 221(45.81) | 963(33.26) | |
Smoking | 230(49.09) | 1298(48.87) | 0.94 |
Drinking | 335(73.32) | 1971(76.69) | 0.111 |
Allergy | 290(65.48) | 884(36.34) | < 0.001 |
Central obesity | 303(62.63) | 1372(48.87) | 0.002 |
Data are shown as mean ± SE or counts (%). Data have been weighted in accordance with the NHANES protocol. |
NHANES, National Health and Nutrition Examination Survey. |
Prevalence of sinusitis among United States adults
The prevalence of sinusitis among adults in the United States, stratified by BMI (normal weight, overweight and obesity) or by WC (non-central obesity, central obesity), is illustrated in Fig. 2. The normal weight group (12.24%) and overweight group (12.05%) exhibited a similar prevalence of sinusitis. However, the group classified as obese (18.67%) or with central obesity (18.1%) exhibited a higher prevalence of sinusitis compared to their counterparts.
Association of sinusitis with BMI and BMI categories
The results of multivariate analysis of a systemic adipose indicator BMI or its categories (normal weight, overweight, obesity), and sinusitis are presented in Table 2. In the unadjusted model, each 1 kg/ m2 increase in BMI was associated with an approximately 4% increased odds of sinusitis, which remained basically unchanged after adjusting for potential confounders in model 1 and model 2. The obesity group showed a significant association with 69% increased odds of sinusitis compared to the normal weight group in the unadjusted model. After adjusting for demographic factors, the odds of sinusitis increased by 81% in obese individuals compared to those with a normal weight. Additionally, when adjusted for smoking, drinking, and allergy, the odds of sinusitis slightly decreased to 77% in obese individuals. However, no significant distinction was observed between overweight and normal weight individuals in terms of sinusitis.
Table 2
Multivariate analysis of sinusitis with BMI and BMI categories in adults
| All participants(N = 3203) |
Unadjusted | Model 1 | Model 2 |
Odds ratio (95% confidence interval) |
BMI (continuous) | 1.044 (1.022–1.065) | 1.043 (1.020–1.067) | 1.043 (1.017–1.070) |
BMI categories | | | |
Normal weight | 1.0 | 1.0 | 1.0 |
Overweight | 0.99 (0.65–1.49) | 1.13 (0.73–1.75) | 1.1 (0.71–1.71) |
Obesity | 1.69 (1.13–2.53) | 1.81 (1.16–2.82) | 1.77 (1.12–2.81) |
Model 1 adjusted for demographic factors: age, sex, race, educational level, and income. |
Model 2 further adjusted for smoking, drinking, and allergy. |
BMI, Body Mass Index. |
Association of sinusitis with WC, HPF and central obesity
Multivariate analysis was conducted to examine the correlations between WC, HPF, central obesity, and sinusitis. The results are shown in Table 3. In unadjusted model, each 1 cm increase in WC, a local adipose indicator, was associated with a 1% increase in the odds of sinusitis. In model 1 and model 2, this association increased to 2%. Similarly, HPF exhibited a significant association with sinusitis, resulting in an increased odds of 28%, 40%, and 37% for every 1% rise in HPF under the unadjusted model, model 1, and model 2 respectively. Meanwhile, compared to the non-central obesity group in model 2, the central obesity group was found to be associated with a 57% increase in odds of sinusitis. Furtherly, considering the dissimilarities in body fat distribution between males and females, we conducted sex-stratified analyses to explore potential modifications by gender on the association between local adipose indicators and sinusitis. The association between sinusitis and WC was found to be positive in both unadjusted and adjusted models for females, while this association was only observed in the unadjusted model for males. Additionally, sinusitis was associated with HPF in both unadjusted and adjusted models for males and females. Only female subjects with central obesity showed a significant association with sinusitis compared to their counterparts.
Table 3
Multivariate analysis of sinusitis with HPF and WC in all adults and adults stratified by sex
| All participants(N = 3203) | Male(N = 1645) | Female(N = 1558) |
| Unadjusted | Model 1 | Model 2 | Unadjusted | Model 1 | Model 2 | Unadjusted | Model 1 | Model 2 |
| Odds ratio (95% confidence interval) |
HPF (continuous) | 1.28 (1.1–1.5) | 1.40 (1.21–1.63) | 1.37 (1.16–1.62) | 1.58 (1.26-2) | 1.62 (1.29–2.04) | 1.53 (1.22–1.91) | 1.3 (1.11–1.51) | 1.31 (1.12–1.53) | 1.3 (1.08–1.56) |
WC (continuous) | 1.01 (1.01–1.02) | 1.02 (1.01–1.03) | 1.02 (1.01–1.03) | 1.02 (1.01–1.03) | 1.02 (0.99–1.04) | 1.02 (0.99–1.03) | 1.02 (1.01–1.03) | 1.02 (1.01–1.03) | 1.02 (1.01–1.03) |
Non-central obesity | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 | 1.0 |
Central obesity | 1.74 (1.26–2.41) | 1.6 (1.11–2.31) | 1.57 (1.09–2.26) | 1.51 (1.03–2.21) | 1.33 (0.85–2.08) | 1.3 (0.85–1.98) | 1.68 (1.11–2.55) | 1.75 (1.12–2.73) | 1.69 (1.05–2.73) |
Model 1 adjusted for demographic factors: age, sex, race, educational level, and income. |
Model 2 further adjusted for smoking, drinking and allergy. |
WC, Waist Circumference; HPF, Head Percent Fat. |
Optimal cutoff values for BMI and WC in relation to sinusitis
The optimal cutoff values for BMI and WC, which indicate sinusitis in adults, are presented in Table 4. The optimal cutoff value for BMI indicating sinusitis was found to be 34.97 kg/m2 (entropy: 0.59), with an odds ratio of 2.11 (95% CI, 1.71–2.6). Meanwhile, the optimal cutoff value for WC indicating sinusitis was found to be 103.4 cm (entropy: 0.59), with an odds ratio of 1.71 (95% CI, 1.37–2.13).
Table 4
The optimal cutoff values of BMI and WC indicating sinusitis in adults
| Optimal cutoff value (model entropy) | Sinusitis | Normal | Odds ratio (95% confidence interval) |
BMI | ≤ 34.97(0.59) | 343 | 2332 | 2.11(1.71–2.6) |
> 34.97 | 123 | 405 |
WC | ≤ 103.4(0.59) | 260 | 1862 | 1.71(1.37–2.13) |
> 103.4 | 206 | 875 |
BMI, Body Mass Index; WC, Waist Circumference. |