Table 6.
Factors associated with lymphoplasmacytic lymphoma/Waldenström’s macroglobulinemia risk, basic adjusted, and final stepwise model risk estimates*
| Factor | Cases, No.† | Controls, No.† | Basic adjusted model‡ | Final model§ | ||
|---|---|---|---|---|---|---|
| OR (95% CI) | P | OR (95% CI) | P | |||
| Sjögren syndrome | ||||||
| No | 174 | 6079 | Referent | .003 | Referent§ | .002 |
| Yes | 3 | 9 | 13.2 (3.42 to 50.9) | 14.0 (3.60 to 54.6) | ||
| Systemic lupus erythematosus | ||||||
| No | 270 | 10 470 | Referent | .002 | Referent | .003 |
| Yes | 4 | 24 | 8.73 (2.91 to 26.2) | 8.23 (2.69 to 25.2) | ||
| Serology hepatitis C virus infection | ||||||
| Negative | 201 | 5259 | Referent | .050 | Referent | .075|| |
| Positive | 6 | 95 | 2.70 (1.11 to 6.56) | 2.51 (1.03 to 6.17) | ||
| Hay fever | ||||||
| No | 218 | 7235 | Referent | .022 | Referent | .017 |
| Yes | 64 | 2511 | 0.70 (0.51 to 0.96) | 0.73 (0.54 to 0.99) | ||
| Usual adult weight¶ | ||||||
| Quartile 1 (low) | 88 | 2432 | Referent | .015 | Referent | .024 |
| Quartile 2 | 66 | 2377 | 0.68 (0.49 to 0.95) | 0.71 (0.51 to 0.99) | ||
| Quartile 3 | 91 | 3115 | 0.70 (0.52 to 0.95) | 0.72 (0.53 to 0.98) | ||
| Quartile 4 (high) | 79 | 3299 | 0.60 (0.44 to 0.83) | 0.61 (0.44 to 0.85) | ||
| Duration of cigarette smoking | ||||||
| Nonsmoker | 118 | 4935 | Referent | .145 | Referent | .148 |
| 1–20 years | 44 | 2007 | 1.01 (0.71 to 1.44) | 1.01 (0.71 to 1.45) | ||
| 21–30 years | 39 | 1258 | 1.23 (0.84 to 1.79) | 1.26 (0.86 to 1.84) | ||
| 30–39 years | 46 | 1235 | 1.32 (0.93 to 1.89) | 1.35 (0.95 to 1.94) | ||
| ≥40 years | 57 | 1194 | 1.49 (1.06 to 2.09) | 1.46 (1.04 to 2.05) | ||
| Smoker, duration unknown | 2 | 88 | 1.14 (0.27 to 4.75) | 1.10 (0.26 to 4.66) | ||
| Family history hematological malignancy | ||||||
| No | 177 | 7303 | Referent | .050 | Referent | .060# |
| Yes | 21 | 452 | 1.65 (1.03 to 2.65) | 1.64 (1.02 to 2.64) | ||
| Occupation: medical doctor** | ||||||
| No | 177 | 6970 | Referent | .003 | Referent | .002 |
| Yes | 6 | 43 | 5.23 (2.11 to 12.9) | 5.54 (2.19 to 14.0) | ||
* CI = confidence interval; OR = odds ratio.
† The counts do not add up to the total number of cases/controls due to data missing by design or report.
‡ Adjusted for age, sex, race/ethnicity, and study.
§ Adjusted for age, sex, race/ethnicity, study, Sjögren syndrome, systemic lupus erythematosus, serology hepatitis C virus infection, hay fever, usual adult weight, smoking duration, family history of hematological malignancy, and medical occupation.
|| P value using likelihood ratio test; P value using Wald test .021.
¶ Quartile 1 (<72.6 kg males, <58.1 kg females), quartile 2 (72.6–79.9 kg males, 58.1–64.9 kg females), quartile 3 (80.0–88.9 kg males, 65.0–74.7 kg females), quartile 4 (≥89.0 kg males, ≥74.8 kg females).
# Occupation at any time in life (eight studies) or the longest held occupation (two studies); occupations coded according to the International Standard Classification of Occupations (ISCO), Revised Edition 1968 (53); code 061 = medical doctor.