Risk factors for recurrent preterm birth in multiparous Utah women: a historical cohort study.

OBJECTIVE: To describe risk factors for recurrent preterm birth (PTB) in the second and third birth. DESIGN: Historical cohort study. SETTING: Utah, USA. POPULATION: Women who had their first three singleton live births in Utah between 1989 and 2007 and a preterm first or second birth were included. METHODS: Maternally linked birth records were used. Multivariable-adjusted risk ratios were calculated for recurrent PTB. Results were stratified by spontaneous and indicated PTB and by pattern of birth outcomes. MAIN OUTCOME MEASURES: Risk ratios and 95% confidence intervals for risk factors for recurrent PTB. RESULTS: Among women with PTB in their first or second live birth, recurrent PTB occurred in 21% of second live births (n = 1011/4805) and 22% of third live births (n = 1872/8468). Risk factors for recurrence included short inter-pregnancy interval, underweight prepregnancy body mass index, pre-existing maternal medical conditions, history of PTB at 28-32 weeks of gestation (versus 33-36 weeks), the presence of a fetal anomaly, and young maternal age. Risk factors for spontaneous, but not indicated PTB included young maternal age and less than appropriate gestational weight gain. Risk factors also varied in women experiencing a first versus second recurrence in their third birth. CONCLUSIONS: Risk factors may vary by the clinical subtype of the most recent PTB and the pattern of term and preterm outcomes across births 1-3; some of the risk factors identified in this study may be modifiable through interventions targeted at women in the inter-conception period.

Attention deficit hyperactivity disorder and increased risk of injury.

PURPOSE: This study describes the influence of attention deficit hyperactivity disorder (ADHD) on the incidence rates of selected injuries. METHODS: A retrospective cohort study design was employed using medical claims data from the Deseret Mutual Benefit Administrators (DMBA), a health insurance company for employees of the Church of Jesus Christ of Latter-day Saints (LDS) and their spouses and dependent children. ADHD diagnosis, injury, medication, and demographic data were extracted from claims files during 1998-2005 for all enrollees aged 0-64 years. RESULTS: Incidence rates of ADHD were 1.83 (95% CI 1.68-2.00) times greater in males than females and highest in the age group 5-9 years and income group $80,000 or greater. ADHD increased the risk of selected injuries. The most common injuries involved sprains and strains of joints, then open wounds of the head, neck and trunk, and upper/lower limb, and then fractures of the upper/lower limb. Medication did not significantly protect against injury in ADHD patients. The rate of severe injury (i.e., fracture of skull, neck and trunk; intracranial injury excluding those with skull fracture; and injuries to nerves and spinal cord) was 3.07 (95% CI 2.37-3.98) times more common in ADHD enrollees compared with non-ADHD enrollees. Those with 1, 2, 3, or 4 or more injuries were 1.67 (1.50-1.86), 2.11 (1.75-2.56), 2.63 (1.80-3.84), and 2.94 (1.47-5.87) times more likely to have ADHD, respectively. CONCLUSIONS: ADHD is positively associated with injuries. More severe injuries have a significantly stronger associated with ADHD than less severe injuries.

Multiple sclerosis in Latter Day Saints (Mormons).

BACKGROUND: Compliant members of the Church of Jesus Christ of Latter Day Saints (LDS, Mormons) have a low incidence of heart and lung disease that may relate to their healthy life style. We wished to determine whether multiple sclerosis (MS) was less frequent in this religious body. METHODS: To ascertain this, diagnostic and treatment coding records were accessed from the Deseret Mutual Benefit Administrators (DMBA) for the 6 year period 1997-2002. DMBA is a medical insurance company that provides medical insurance to all employees of LDS Church in the US. This information was combined with prescribing records for disease modifying treatment, principally beta-interferon and Copaxone which are medications specific to MS. RESULTS: Using various search strategies we derived an approximate MS prevalence of 45-64/100,000. CONCLUSION: Comparison with MS rates from Utah and other states of comparable latitude suggest that strict LDS have an MS prevalence that is lower than expected and may reflect their healthy life style.

Cellulitis incidence in a defined population.

A population-based insurance claims database was used to examine cellulitis incidence, anatomical sites of infection, complicating diagnoses, source of health service, and recurrence rates. Insurance claim files were searched for cellulitis ICD-9-CM codes 681.0-682.9. Complications of cellulitis including erysipelas, lymphadenitis, lymphangitis, and necrotizing fasciitis were also identified by ICD-9-CM codes. We found a cellulitis incidence rate of 24.6/1000 person-years, with a higher incidence among males and individuals aged 45-64 years. The most common site of infection was the lower extremity (39.9%). The majority of patients were seen in an outpatient setting (73.8%), and most (82.0%) had only one episode of cellulitis during the 5-year period studied. There was a very low incidence of cellulitis complications, including necrotizing fasciitis. Cellulitis is fairly common, usually treated in outpatient settings, and is infrequently complicated by erysipelas, lymphadenitis, lymphangitis, or necrotizing fasciitis.

Comparison of two methods based on cross-sectional data for correcting corpus uterine cancer incidence and probabilities.

BACKGROUND: Two methods are presented for obtaining hysterectomy prevalence corrected estimates of invasive cancer incidence rates and probabilities of the corpus uterine. METHODS: The first method involves cross-sectional hysterectomy data from the Utah Hospital Discharge Data Base and mortality data applied to life-table methods. The second involves hysterectomy prevalence estimates obtained directly from the Utah Behavior Risk Factor Surveillance System (BRFSS) survey. RESULTS: Hysterectomy prevalence estimates based on the first method are lower than those obtained from the second method through age 74, but higher in the remaining ages. Correction for hysterectomy prevalence is greatest among women ages 75-79. In this age group, the uncorrected rate is 125 (per 100,000) and the corrected rate based on the life-table method is 223 using 1995-97 data, 243 using 1992-94 data, and 228 from the survey method. The uncorrected lifetime probability of developing corpus uterine cancer is 2.6%; the corrected probability from the life-table method using 1995-97 data is 4.2%, using 1992-94 data is 4.5%; and based on prevalence data from the survey method is 4.6%. CONCLUSIONS: Both methods provide reasonable hysterectomy prevalence estimates for correcting corpus uterine cancer rates and probabilities. Because of declining trends in hysterectomy in recent decades, corrected estimates from the life-table method are less pronounced than those based on the survey method. These methods may be useful for obtaining corrected uterine cancer rates and probabilities in areas of the world that do not have sufficient years of hysterectomy data to directly compute prevalence.

High rates of multiple antibiotic resistance in Streptococcus pneumoniae from healthy children living in isolated rural communities: association with cephalosporin use and intrafamilial transmission.

OBJECTIVE: Streptococcus pneumoniae is one of the most clinically significant pathogens with emerging antibiotic resistance. We performed a surveillance study in isolated rural populations of healthy children to estimate the prevalence of pneumococcal resistance and to contrast factors that predict pneumococcal carriage with those that specifically predict resistant pneumococcal carriage. METHODS: The study was conducted in 1998 in 2 rural communities in Utah. Families were recruited directly for participation through community canvassing. Surveillance nasopharyngeal cultures were obtained from children who were younger than 8 years. Antibiotic usage and information on other potential risk factors were obtained from questionnaires and local pharmacy records. Resistance was determined by testing isolates for susceptibility to penicillin, cefaclor, trimethoprim-sulfamethoxazole, erythromycin, ceftriaxone, and trovafloxacin. Selected resistant isolates were characterized further by serotyping, pulsed field gel electrophoresis, and Southern blot with DNA probes specific for the pneumococcal lytA gene and for antibiotic resistance genes. RESULTS: In April 1998, surveillance nasopharyngeal cultures were obtained from 368 children aged

Occupational exposure to formaldehyde and wood dust and nasopharyngeal carcinoma.

OBJECTIVES: To investigate whether occupational exposures to formaldehyde and wood dust increase the risk of nasopharyngeal cancer (NPC). METHODS: A multicentered, population based case-control study was carried out at five cancer registries in the United States participating in the National Cancer Institute's SEER program. Cases (n=196) with a newly diagnosed NPC between 1987 and 1993, and controls (n=244) selected over the same period from the general population through random digit dialing participated in structured telephone interviews which inquired about suspected risk factors for the disease, including a lifetime history of occupational and chemical exposure. Histological type of cancer was abstracted from clinical records of the registries. Potential exposure to formaldehyde and wood dust was assessed on a job by job basis by experienced industrial hygienists who were blinded as to case or control status. RESULTS: For formaldehyde, after adjusting for cigarette use, race, and other risk factors, a trend of increasing risk of squamous and unspecified epithelial carcinomas was found for increasing duration (p=0.014) and cumulative exposure (p=0.033) but not for maximum exposure concentration. The odds ratio (OR) for people cumulatively exposed to >1.10 ppm-years was 3.0 (95% confidence interval (95% CI) 1.3 to 6.6) compared with those considered unexposed. In analyses limited to jobs considered definitely exposed, these trends became stronger. The associations were most evident among cigarette smokers. By contrast, there was no association between potential exposure to formaldehyde and undifferentiated and non-keratinising carcinomas. There was little evidence that exposure to wood dust increased risk of NPC, as modest crude associations essentially disappeared after control for potential exposure to formaldehyde. CONCLUSIONS: These results support the hypothesis that occupational exposure to formaldehyde, but not wood dust, increases risk of NPC. This association seems to be specific to squamous cell carcinomas. Established cohorts of workers exposed to formaldehyde and wood dust should continue to be monitored for NPC and other respiratory cancers. Future studies of NPC should take into account histological type in assessing risk from environmental and host factors.

Explaining the difference in prostate cancer mortality rates between white and black men in the United States.

OBJECTIVES: Black men have a twofold increased risk of dying of prostate cancer compared to white men. We assessed the extent to which differences in stage and grade at diagnosis, age, multiple primary cancers, and the first course of cancer-directed therapy influence the likelihood of prostate cancer death among diagnosed cases. METHODS: Incidence-based mortality (IBM) is a method that involves tracking disease cases from diagnosis to death, such that the mortality event is linked to factors identified with the disease at the time of diagnosis (eg, tumor stage and grade). We applied the IBM method to prostate cancer data from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. RESULTS: Of men diagnosed with prostate cancer, blacks have a significantly greater chance of dying from the disease than do whites. However, once adjustment has been made for stage and grade at diagnosis, age, number of primary cancers, and initial treatment, no difference in the likelihood of prostate cancer mortality between the two races was found. Differences in stage and grade at diagnosis, age, number of primary cancers, and initial treatment each contributed significantly to the greater chance of dying of prostate cancer for black men than for white men. CONCLUSIONS: The results of IBM analysis suggest that black men do not have a statistically greater chance of prostate cancer mortality than white men after adjusting for differences in stage and grade, age, number of primary cancers, and treatment. Later stage at diagnosis is the primary reason for the higher likelihood of prostate cancer mortality among black men compared to white men.

Errors and biases in the diagnosis of cancer of the lung and their influence on risk estimates.

When diagnosed as primary lung cancer, metastases from the abdomen, plus false negative cases have little effect on epidemiology studies of male smokers, but may result in a severe dilution of the lung cancers among women and nonsmokers. We have attempted to quantitate this handicap for epidemiological studies using two approaches. The relative frequency of diagnosed primary lung and abdominal cancer among males, women, and nonsmokers differs substantially and is used here to calculate magnitude. The second approach postulates that the ratio of nonsmokers among persons with squamous cell lung cancer and primary adenocarcinoma of the lung would be constant by sex if there were no distortion by abdominal metastases. These two approaches indicate that the much higher ratio of metastatic disease diagnosed as primary lung cancer among nonsmoking women (factor of 15 to 20), makes it more difficult to identify an environmental carcinogen among women or nonsmokers than among male smokers in case-control studies.

Diet and nasopharyngeal cancer in a low-risk population.

Asian studies have reported that risk of nasopharyngeal cancer (NPC) is increased in individuals who frequently consume salted fish, which contains high levels of N-nitroso compounds. As part of a collaborative, population-based, case-control study in the U.S., where the annual incidence of the disease is low, we investigated whether dietary intake of preformed nitrosamines or nitrosamine precursors, or of antioxidants including vitamin C and carotenoids, was associated with altered risk of NPC overall, or of specific histologic subtypes of disease. Cases (n = 133) identified at 5 population-based cancer registries and controls (n = 212) identified through random digit dialing completed a telephone interview and self-administered food frequency questionnaire. Dietary exposures were expressed as quartiles of intake, and odds ratios (ORs) calculated using the lowest quartile of intake as the reference category. Risk of non-keratinizing and undifferentiated tumors of the nasopharynx was increased in frequent consumers of preserved meats, which contain high levels of added nitrites. ORs in the 2nd, 3rd and highest quartile were 1.99, 4.35 and 4.59, although 95% confidence intervals did not exclude 1.0. Risk of differentiated squamous cell carcinoma, but not other histologic types, was significantly reduced in individuals with vitamin C intake above the lowest quartile (ORs 0.30, 0.33 and 0.30 in the 2nd, 3rd and highest quartiles, respectively). This association was markedly stronger among non-smokers and former smokers than among current smokers. Finally, individuals who reported consuming supplemental vitamins were at an approximately 50% reduced risk of NPC. Our results indicate that future studies should consider the effects of dietary risk factors on the risk of specific histologic subsets of NPC, and not assume that the disease is etiologically homogeneous.

Variation in the diagnosis of upper respiratory tract infections and otitis media in an urgent medical care practice.

BACKGROUND: Variation among hospitalized medical conditions have been reported previously, but there is little information on variation among physicians for medical conditions that constitute a substantial part of ambulatory care. OBJECTIVE: To measure variation in the diagnosis of 2 common medical conditions, otitis media (OM) and upper respiratory tract infections (URIs) in an urgent care practice. DESIGN: Estimate the variation in the incidence of new diagnoses of OM and URIs among 19 physicians working at 2 urgent care clinics between January 1, 1995, and March 31, 1995. Patients are seen in order of arrival, and assignment to each physician is random. PARTICIPANTS AND SETTING: Two urgent care clinics staffed by the same 19 physicians. During the 3-month study period, 21,259 patients were seen at the 2 clinics; of these, 1839 (8.65%) received a diagnosis of first time OM; and 8020 (37.73%), of an URI. MAIN OUTCOME MEASURE: Incidence of new diagnoses of OM and URI estimated as a proportion of all diagnoses for each individual physician. RESULTS: There was substantial variation between physicians in the diagnosis of OM, ranging from a low of 4.2% to a high of 21.8%. There was less variation in the diagnosis of URI (31.7%-48.4%). Some physicians with a low incidence of OM or URI diagnoses had increased the proportion of diagnoses in the other diagnostic category. For OM the variation was greatest for children younger than age 5 years, but substantial variation was also found in adults. For URIs the variation was more uniform across all age groups. The variation was not explained by type of specialty training or years in medical practice. CONCLUSIONS: There is substantial variation between physicians in their diagnosis of OM and URI in an urgent care setting. This variation has implications for cost of diagnosing and treating these conditions, the training of physicians, and our understanding of the treatment of OM.

Nasopharyngeal cancer in a low-risk population: defining risk factors by histological type.

Nasopharyngeal cancer (NPC) is a major public health problem in parts of Southeast Asia and North Africa, but is rare among whites and blacks. Although infection with the EBV and genetic susceptibility appear to play large roles in high-incidence populations, migrant studies suggest that environmental factors may also be important. Aside from the high risks associated with ingestion of salted fish, surprisingly few other risk factors have been established from studies in endemic areas. We studied a low-incidence population to determine whether tobacco use, alcohol consumption, and certain medical conditions and treatments are related to NPC and to examine variations in risk by histology. We reasoned that new relationships might be best identified in the absence of strong causal pathways, such as intake of preserved foods and genetic susceptibility. A population-based case-control study was conducted from 1987 to 1993 at five cancer registries in the United States: western Washington, metropolitan Detroit, Connecticut, Iowa, and Utah. Controls were identified by random digit dialing and frequency matched to the gender and age distribution of cases at each registry. Telephone interviews were completed by 231 cases and 246 controls. We observed a strong dose-response relationship between cigarette smoking and risk of differentiated squamous cell carcinoma (test for trend, P < .001). The highest risk [odds ratio (OR), 6.5; 95% confidence interval (CI), 2.0-21.3] occurred among current smokers with a history of more than 60 pack-years. In contrast, there was no evidence that undifferentiated or nonkeratinizing carcinomas were associated with cigarette smoking. Similarly, a significant increase in risk was observed for the heaviest alcohol consumers (21 or more drinks/week) only for differentiated squamous cell carcinomas (OR, 2.9; 95% CI, 1.2-6.9). The associations with cigarettes and alcohol appeared to be stronger among persons 50 years or older. There was a suggestion that diagnosis with infectious mononucleosis (a marker of late infection with EBV) is linked with decreased NPC risk (OR, 0.4; 95% CI, 0.1-1.1). This report indicates that over two-thirds of differentiated squamous cell NPC cases arising in older persons in the United States can be accounted for by cigarettes and alcohol, but leaves unexplained cases arising in the young and carcinomas of undifferentiated or nonkeratinizing histology. Future studies of NPC need to take into account histology and age in evaluating these and other environmental and genetic risk factors.

Is diabetes mellitus a risk factor for ovarian cancer? A case-control study in Utah and Washington (United States).

Insulin resistance characterizes non-insulin dependent diabetes (NIDDM). Insulin resistance may coexist in clinical syndromes with hyperestrogenism and hyperandrogenism, suggesting that the ovary may be sensitive to effects of insulin. In addition, insulin-like growth factor-I receptors, which are capable of binding insulin, have been identified in ovarian cancer tissue and are proposed to regulate cell growth. We evaluated the association between a history of diabetes mellitus and ovarian cancer in a case-control study in seven counties in Washington and in Utah (United States) during the years 1975-87. Cases included women newly diagnosed with ovarian cancer over a five-year period who were identified through population-based cancer reporting. Controls similar to cases with regard to age and county of residence were identified via household surveys or random digit dialing. The study included 595 cases and 1,587 controls. Twenty-seven cases (4.5 percent) and 72 controls (4.5 percent) reported a history of diabetes. Logistic regression analysis of the association between diabetes and ovarian cancer controlling for age, body mass index, and race resulted in an odds ratio (OR) of 0.9 (95 percent confidence interval [CI] = 0.6-1.5). The OR was not changed with further controlling for prior oral contraceptive use or prior pregnancy. None of the 20 women with nonepithelial tumors (15 of which were stromal tumors) had a history of diabetes (upper CI = 4.0). These results, together with findings of two earlier cohort studies, do not support the hypothesis that diabetes is a risk factor for epithelial ovarian cancer.

The incidence of iliac, femoral, and popliteal artery aneurysms in hospitalized patients.

PURPOSE: Previous studies have attempted to determine the incidence and mortality rate of abdominal aortic aneurysms in a variety of populations; however, the incidence of iliac, femoral, and popliteal artery aneurysms have not been established. The objective of this study was to determine the incidence of lower extremity aneurysms in hospitalized patients in the state of Utah, which has a population at low risk for cardiovascular disease, atherosclerosis, and smoking, and to compare the results with the incidence in the United States. METHODS: Incidences of iliac, femoral, and popliteal artery aneurysm in Utah were determined over a 6-year period, with data obtained via diagnostic codes from the Utah Hospital Association. The incidence of iliac, femoral, and popliteal artery aneurysms in the United States hospital population was calculated by use of National Hospital Discharge Summary 1990 data, a complex sample of nonfederal short-stay hospitals in the United States, which provides the most comprehensive database of health statistics in the United States. RESULTS: The incidence of iliac femoral/popliteal artery aneurysms in hospitalized Utah men is 3.76 and 4.85 per 100,000 population, respectively. In American men, iliac and femoral/popliteal artery aneurysm incidences are 6.58 and 7.39 per 100,000 population, respectively. Incidences among hospitalized women in Utah are 0.24 and 1.07 per 100,000; incidences in women in the United States are 0.26 and 1.00 per 100,000, respectively. The incidence of nonaortic peripheral aneurysms among hospitalized patients in Utah is lower than in the United States. The rate ratios (Utah/United States) for incidences of iliac, femoral, and popliteal artery aneurysms in men are 0.57 and 0.66, respectively (p < 0.05). No statistical difference is seen between incidences in women in Utah and the United States (p > 0.05)-ratios of 0.93 and 1.06, respectively. CONCLUSION: This study validates the traditional belief that iliac, femoral, and popliteal artery aneurysms are much less frequent, at least in hospitalized patients, than previously published incidences of abdominal aortic aneurysms.

Surgical trends in the treatment of diseases of the lumbar spine in Utah's Medicare population, 1984 to 1990.

Chronic low back pain is a major source of disability in this country. The rate of surgical treatment for back disorders varies between small geographic areas in the northeastern United States. A statewide database was utilized to determine rate of surgery for mechanical low back problems in Utah's Medicare population from 1984 to 1990. The average surgery rate for Medicare enrollees was 274.7 per 100,000, and the Utah laminectomy and discectomy rates were at least 20% higher than the U.S. average. Back surgery rates rose by 55% over the study period, primarily because of increasing rates of surgery for spinal stenosis. There was statistically significant variation in surgery rates among regions in the state, with the highest region having a rate 50% greater than the lowest region. Rates of surgery for spinal stenosis had more variation than those for herniated disc surgery. There was no significant correlation between the number of surgeons performing back surgery and the rate of surgery. The variation and increase in back surgery rates in Utah's Medicare population are likely related to changes in the use of surgery for treatment of spinal stenosis and not to an increase in the number of back surgeons. Further investigation is needed to understand better the reasons for the observed increase in back surgery rates.

Maternal exposure to N-nitrosatable drugs as a risk factor for childhood brain tumours.

BACKGROUND: Animal models suggest that compounds containing a nitrosyl group (N-nitroso compounds (NNO)) can act as potent transplacental carcinogens. Many common drug formulations have the potential to undergo nitrosation in vivo. The association between maternal use of nitrosatable drugs during pregnancy and development of brain tumours in the offspring was examined in a SEER-based case-control study. METHODS: Maternal exposure to nitrosatable drugs during pregnancy was compared among 361 childhood brain tumour cases and 1083 matched controls recruited through random-digit dialing. RESULTS: There was no increase in risk observed for childhood brain tumours overall (OR = 1.15; 95% CI: 0.69-1.94) or for astrocytomas individually (OR = 1.16; 95% CI: 0.50-2.69). A slight elevation in risk was noted for medulloblastomas (OR = 1.47; 95% CI: 0.28-7.62) and 'other' tumours (OR = 1.27; 95% CI: 0.56-2.86), however, both estimates were based on small numbers. CONCLUSIONS: Our findings suggest that no increased risk of childhood brain tumours was associated with maternal exposure to nitrosatable drugs. The study results should be viewed with caution given the imprecision of the point estimates as well as the lack of data on specific timing and dosage of exposure and degree of nitrosatability of drugs taken.