ABSTRACT
Radiation exposure is a possible predisposing factor for monoclonal gammopathy of undetermined significance (MGUS), but the association has been uncertain. We investigated the relationship between radiation exposure and MGUS prevalence by using data from the M-protein screening for Nagasaki atomic bomb survivors between 1988 and 2004. Radiation exposure was assessed by exposure distance from the hypocenter and exposure radiation dose. We computed prevalence ratios (PRs) and the 95% confidence intervals (CIs) adjusting for exposure age and sex. A total of 1082 cases of MGUS were identified from 52 525 participants. MGUS prevalence was significantly higher in people exposed at distance within 1.5 km than beyond 3.0 km (PR, 1.4; 95% CI, 1.1-1.9) among those exposed at age 20 years or younger, but it was not found among those exposed at age 20 years or older. MGUS prevalence was also significantly higher in people exposed to more than 0.1 Gy than those exposed to less than 0.01 Gy (PR, 1.7; 95% CI, 1.0-2.8) among those exposed at age 20 years or younger. Thus, people exposed at younger age exhibited a significantly high risk of MGUS when exposed to a high radiation dose. There was no clear association between radiation exposure and the malignant progression of MGUS. Further detailed analysis is needed.
Subject(s)
Nuclear Weapons , Paraproteinemias/epidemiology , Radiation Injuries/epidemiology , Survivors/statistics & numerical data , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Child , Female , Humans , Japan/epidemiology , Male , Middle Aged , Paraproteinemias/etiology , Prevalence , Radiation Dosage , Radiation Injuries/complications , Risk Factors , Young AdultABSTRACT
OBJECTIVE: To assess the prevalence of monoclonal gammopathy of undetermined significance (MGUS) in a large Japanese population. PARTICIPANTS AND METHODS: From October 1, 1988, to March 31, 2004, a total of 52,802 (of 71,675) Japanese survivors of the atomic bomb explosion in Nagasaki City, Japan, were screened for M protein. The youngest participant was 42.3 years as of October 1, 1988. A 2-step screening was performed with a serum protein electrophoresis followed by immunoelectrophoresis and a quantitative determination of serum concentration of immunoglobulins. Twenty-one patients who were diagnosed for the first time at the time of screening as having multiple myeloma and Waldenström macroglobulinemia were excluded from analyses. Age- and sex-specific prevalence rates of MGUS were calculated. RESULTS: Monoclonal gammopathy of undetermined significance was identified in 1088 of the 52,781 study participants. The overall prevalence of MGUS was 2.1% (95% confidence interval [CI], 1.9%-2.2%) in the total population screened and 2.4% (95% CI, 2.0%-2.6%) in those 50 years or older. The prevalence was significantly higher in men than in women (2.8% vs 1.6%; age-adjusted odds ratio, 2.0; 95% CI, 1.8-2.3; P less than .001). In both sexes, the prevalence rose with increasing age from 1.0% in participants aged 42 to 49 years, 1.9% in those 50 to 59 years, 2.6% in those 60 to 69 years, and 3.0% in those 70 to 79 years, to 4.4% in those 80 years and older. The heavy chain isotypes of immunoglobulin were IgG in 73.6% of patients, IgA in 17.7%, IgM in 7.5%, and oligoclonal gammopathies in 1.1%. CONCLUSION: The prevalence of MGUS is lower in this Japanese population than that reported in Western countries among people older than 60 years, especially among women.
Subject(s)
Asian People/statistics & numerical data , Paraproteinemias/epidemiology , Adult , Age Distribution , Aged , Aged, 80 and over , Cohort Studies , Explosions , Female , Humans , Japan/epidemiology , Male , Middle Aged , Nuclear Weapons , Paraproteinemias/diagnosis , Prevalence , Sex Distribution , Survivors/statistics & numerical data , Urban HealthABSTRACT
To elucidate the effects of the bombing on the atomic bomb survivors' mental health, a mental health survey was conducted using a 12-item version of the General Health Questionnaire (GHQ-12) and a mail survey on atomic bomb exposure conditions and lifestyle using a self-administered questionnaire. A total of 3526 atomic bomb survivors in Nagasaki responded and a high GHQ-12 score, as defined when the responses to four or more items were positive, was observed in 296 (8.4%) subjects. It was indicated that the risk of a high GHQ-12 score will decrease 0.98-fold with every 1-year increase in age, and will increase 1.45-fold and 1.70-fold in those who lost family members due to the bombing and those who had acute symptoms, respectively, compared with those who did not. It was indicated that the atomic bomb exposure has affected survivors' mental health and that the care of their mental health is important.
