Factors affecting the prevalence of chronic diseases in Palestinian people: an analysis of data from the Palestinian Central Bureau of Statistics.

This study determined whether there are significant differences in the prevalence of diabetes, hypertension, cardiovascular disease (CVD) and cancer among Palestinians with respect to different demographic variables using secondary data from the Palestinian Central Bureau of Statistics. Living in the Gaza Strip was a protective factor, with this group being 21% less likely to have diabetes, 35% less likely to have hypertension, and 48% less likely to have CVD than those living in the West Bank. No significant difference was found for cancer. Being a refugee was a significant risk factor for diabetes and CVD while being married/engaged or divorced/ separated/widowed was a risk factor for diabetes and hypertension. Gender was a risk factor for hypertension with females being 60% more likely to have hypertension than males. Living in a rural setting was protective against hypertension. As expected, age was a risk factor for diabetes, hypertension and CVD; the magnitude of this increased risk was alarming, 36 to 434 times greater in those aged 40-65 years compared with those aged 0-19 years.

Preventable risk factors for nasal cancer.

PURPOSE: To determine preventable risk factors for cancers of the nasal cavity and paranasal sinuses in the United States, we analyzed data from the population-based, case-control Selected Cancers Study. METHODS: Cases were men born between 1929 and 1953 who were diagnosed with primary nasal cancer between 1984 and 1988 and identified from population-based cancer registries; we narrowed the cohort to 70 subjects whose diagnosis of nasal cancer was confirmed by pathology review. All living controls interviewed for the Selected Cancers Study were included as the comparison group (n = 1910); they were recruited by random-digit dial telephone and were frequency-matched to the lymphoma cases of the Selected Cancers Study by geographic area and age. Both cases and controls were interviewed by telephone. RESULTS: Logistic regression analyses showed that cases were 2.5 times more likely than controls to have smoked cigarettes [95% confidence interval (CI) = 1.1-5.3], and 2.2 times more likely to have worked in selected occupations, including lawn care, forestry, and maintenance of highway right-of-way areas (CI = 1.2-3.7). These occupations may cause workers to be exposed to pesticides or herbicides. The population attributable risk (PAR) was 53% for having ever smoked cigarettes. CONCLUSIONS: The study results suggest that among U.S. men, some nasal cancer may be preventable by avoiding cigarette smoking.

Breast cancer and electromagnetic fields--a review.

PURPOSE: Several statements have been issued to the effect that no consistent, significant link has been demonstrated between cancer and electromagnetic fields (EMF). However, there continues to be much interest in a possible association with breast cancer, in part because breast cancer risk is substantially higher in industrialized countries than in other areas, and electric power generation and consumption is one of the hallmarks of industrialized societies. In 1987, Stevens proposed a biological mechanism whereby two products of electric power generation, EMF and light at night, might contribute to mammary carcinogenesis through inhibition of melatonin. METHODS: We conducted a comprehensive review of the epidemiologic literature and hypothesized mechanisms pertaining to EMF exposure and the risk of breast cancer, in order to assess whether or not there was evidence to suggest a link between EMF and breast cancer. RESULTS: Some occupational epidemiological studies have demonstrated an increased incidence of breast cancer among mainly male electrical workers. It has been difficult to study women, as few are employed in these types of occupations. In all, there have been eleven occupational studies related to breast cancer in women, and statistically significant risk ratios have been observed: 1.98 for pre-menopausal women in occupations with high EMF exposure in one study, 2.17 in all women who worked as telephone installers, repairers, and line workers in another study, and 1.65 for system analysts/ programmers, 1.40 for telegraph and radio operators, and 1.27 for telephone operators in a third study. However, six of the studies did not find any significant effects and two found effects only in subgroups. The results of the eight studies of residential exposure and four electric blanket studies have been inconsistent, with most not demonstrating any significant association. However, this might be attributed, at least to some extent, to difficulties in assessing residential exposure in these studies, as well as other methodological considerations. CONCLUSIONS: The biologic plausibility of an association between EMF and breast cancer, coupled with suggestive data from occupational studies and unexplained high incidence rates of breast cancer, suggests that further investigation of this possible association is warranted.

Perceived barriers and recommendations concerning hormone replacement therapy counseling among primary care providers.

OBJECTIVE: To increase our understanding of the factors that impede or promote counseling about hormone replacement therapy, we asked clinicians to provide information concerning barriers and strategies to promote counseling. DESIGN: We asked clinicians to consider two different scenarios: (1) what they do in they current practice and (2) what they would do if their health care systems implemented the United States Preventive Services Task Force recommendation regarding hormone replacement therapy counseling. A total of 49 of 50 invited clinicians participated in one of six focus group interviews (three women's groups and three men's groups). Our analysis consisted of four steps: (1) identifying segments and classifying them into themes, (2) categorizing themes into topic areas, (3) establishing a final consensus of themes and topics, and (4) ascertaining similarities and contrasts among groups. Transcripts of sessions were analyzed across groups for themes using a text-based analysis system. Conceptualization of themes was derived using a system model of preventive care. Interrater agreement before consensus was good: Kappa (kappa) ranged from 0.70 to 1.00. RESULTS: For current practice, identified barriers included lack of information about risks and benefits, unique challenges of counseling, and lack of resources to conduct counseling. The major strategies suggested were to develop and distribute patient education materials. Discussions about barriers to implementing the United States Task Force recommendation focused on lack of information and resources. CONCLUSIONS: Suggested strategies were multiple, involving individual-, relationship-, and system-level interventions. We expect the strategies identified to be supportive of future efforts to promote counseling for hormone replacement therapy.

Risk factors for non-Hodgkin's lymphoma according to family history of haematolymphoproliferative malignancies.

BACKGROUND: Aetiological profiles of non-Hodgkin's lymphoma (NHL) may differ depending upon whether the disease is inheritance-related or sporadic. Because familial risk (a probable surrogate of inheritance-relatedness) of NHL is influenced by haematolymphoproliferative malignancies (HLPM), we evaluated whether non-familial risk factors differ between NHL with and without a family history of HLPM, using the Selected Cancers Study data. METHODS: Cases were 1511 men aged 31-59 and diagnosed with NHL during 1984-1988. Controls were men without NHL, frequency-matched to cases by age range and cancer registry (n = 1910). These groups were compared: cases with a family history of HLPM and without, and controls without such a family history. RESULTS: Polytomous logistic regression analyses showed that the odds ratio (OR) estimates of homosexual behaviour were 18.2 (95% confidence interval (CI) : 4.8-69.4) and 5.6 (95% CI : 3.3-9.5) for NHL with and without a family history of HLPM, respectively. The corresponding estimates were 3.9 (95% CI : 1.7-8.9) and 2.2 (95% CI : 1.5-3.1) for history of enlarged lymph nodes. Variables only related to NHL with a family history were use of heroin (OR = 15.6, 95% CI : 3.4-70.4), exposure to a chlorinated hydrocarbon pesticide (OR = 2.3, 95% CI : 1.0-5.0), occupational exposure to plywood, fibreboard or particleboard (OR = 2.0, 95% CI : 1.2-3.4) and history of liver diseases (other than hepatitis or cirrhosis) (OR = 6.5, 95% CI : 1.2-36.2). The association between homosexual behaviour and NHL among men with a family history was stronger for those aged 31-44, especially for B-cell type of the disease. CONCLUSIONS: This study suggests differences in the risk factor profiles between NHL with and without a family history of HLPM. The higher risks of NHL for homosexual behaviour and heroin use, surrogates of HIV infection, in men with a family history of HLPM imply that genetic susceptibility may be influential on the occurrence of HIV-related NHL.

Exposure to N-nitroso compounds in a population of high liver cancer regions in Thailand: volatile nitrosamine (VNA) levels in Thai food.

The recent case-control studies in Thailand indicate that a high incidence of liver cancer in Thailand has not been associated with common risk factors such as hepatitis B infection, aflatoxin intake and alcohol consumption. While the infestation by the liver fluke Opisthorchis viverrini (OV) accounted for the high risk in north-east Thailand, there was no such exposure in the other regions of the country where the incidence of liver cancer is also high. Case-control studies suggest that exposure to exogenous and possibly endogenous nitrosamines in food or tobacco in betel nut and cigarettes may play a role in the development of hepatocellular carcinoma (HCC), while OV infestation and chemical interaction of nitrosamines may also be aetiological factors in the development of cholangiocarcinoma (CCA). Over 1800 samples of fresh and preserved food were systematically collected and tested between 1988 and 1996. All the food items identified by anthropological studies to be consumed frequently in four major regions of Thailand were analysed for volatile nitrosamines using gas chromatography combined with a thermal energy analyser. Relatively high levels of N-nitrosodimethylamine (NDMA), N-nitrosopiperidine (NPIP) and N-nitrosopyrrolidine (NPYR) were detected in fermented fish ("Plasalid"). NDMA was also detected at levels ranging from trace amounts to 66.5 microg/kg in several salted and dried fish ("Larb-pla" and "Pla-siu"). NDMA and NPYR were frequently detected in several vegetables, particularly fermented beans ("Tau-chiau") at levels ranging between 1 and 95.1 microg/kg and 0-146 microg/kg, respectively. The possible role of nitrosamines in Thai food in the aetiology of liver cancer (HCC, CCA) is discussed.

Worksite breast cancer screening programs: a review.

1. Breast cancer is a major health problem amenable to secondary prevention for reducing morbidity and mortality. 2. Given the large and increasing numbers of women in the workplace, breast cancer prevention and control measures should be included in workplace health promotion programs. However, despite the increasing prevalence of worksite health promotion programs in the United States, the prevalence of breast cancer programs in the workplace has been decreasing. 3. Despite the limited evaluative research of worksite breast cancer screening programs, a number of important conclusions conducted thus far. 4. Additional scientifically rigorous evaluation studies of worksite health programs for the early detection of breast cancer are needed, and additional innovative workplace programs aimed at increasing breast cancer screening need to be developed.

Patient delay in seeking help for potential breast cancer.

BACKGROUND: Patient delay in seeking medical attention could be a contributing cause in a substantial number of breast cancer deaths. The purpose of this study was to identify factors associated with long delay in order to identify specific groups in need of more intensive education regarding the signs of breast cancer and the importance of early treatment. METHODS: A study of 162 women with potential breast cancer symptoms was done in the area of Worcester, MA. Two methods of analysis were used. A case-control approach was used where the outcome variable was categorized into two groups of longer and shorter delay, and a survival analysis was used where the outcome variable was treated as a continuous variable. RESULTS: It was found that women with increasing symptoms were more likely to delay than women whose symptoms either decreased or remained the same. Women performing monthly breast self-examination and/or receiving at least bi-annual mammograms were much less likely to delay than women who performed breast self-examination or received mammograms less often. It was also found that women using family practitioners were less likely to delay than women using other types of physicians. CONCLUSIONS: Patient delay continues to be a major problem in breast cancer, as 16% of the women here delayed at least two months before seeking help. This study presented a new and improved method for defining patient delay, which should be explored further in larger studies.

To screen or not to screen: the issue of breast cancer screening in older women.

INTRODUCTION: The United States Preventive Services Task Force (USPSTF) recommends that women aged 50-69 receive timely breast cancer screening, but does not make a recommendation for women aged 70 and older. Our purpose is to assess the relationship between age and breast cancer screening trends, and to consider the issue of breast cancer screening of women 70 years of age and older in light of demographics, disease burden, life expectancy, and activity level. METHODS: Data were analyzed from the state-based Behvioral Risk Factor Surveillance System (BRFSS) and the National Health Interview Survey (NHIS) on breast cancer screening practices and activity limitation status of women 50 and older. RESULTS: The percentage of women who reported receiving mammography and clinical breast examination within two years was lower among older women compared with younger women, and the gap has widened over time. In 1991-92, 61.4% of women 50-69 received screening within two years, compared to 49.5% of women 70 and above, while in 1997-98, the percentages were 71.1 and 56.7, respectively. Among both age groups and in both time periods, those unable to perform a major activity of daily living were less likely to report receiving mammography within two years than those with no limitation, and the gap was much wider in the elderly. Most (62.7%) women 70 and older reported having no activity limitation; only 5.5% reported being unable to perform a major activity. DISCUSSION: These results suggest that elderly women are less likely than younger women to receive timely breast cancer screening. The USPSTF does not recommend continued screening in elderly women because most studies of breast cancer efficacy included inadequate numbers of these women. Few, if any, studies have yielded evidence that screening is ineffective in women 70 and over. Given the higher breast cancer incidence and mortality seen in elderly women, as well as the increased life expectancy with little or no activity limitation seen among today's elderly, consideration should be given to including elderly women in the recommendation to receive timely breast cancer screening. Since surgical and adjuvant therapy for breast cancer in older women has less complications than therapy for other cancers of the elderly, the cost-benefit ratio for breast cancer screening in this age group may prove to be more promising.

Liability in breast cancer screening.

The U.S. breast cancer mortality rate has risen over the past 29 years in women 50 years of age and older. This is surprising in light of the fact that the disease is curable when detected early through mammography together with clinical breast examinations (CBE). One major problem is that many women are not being screened. Only about one-third of women 50 years of age and older are receiving yearly screening mammograms, despite published guidelines. Regarding CBE, more women are receiving them, but there is room for improvement. The main reasons given by women for not having a mammogram are: 1) their physicians did not recommend it; 2) they did not know they needed one; or 3) they did not have any breast problems. These responses reflect a lack of awareness of breast cancer screening recommendations and indicate that women are not being given adequate information about breast cancer from their physicians. This paper will explore the medical malpractice literature in order to discuss the question of whether physicians should be liable for failing to inform their female patients.

Disparities in breast cancer screening: is it ethical?

Breast cancer incidence and mortality rise dramatically as women get older. Approximately 48% of newly diagnosed breast cancers occur in women 65 and over, while nearly 57% of the breast cancer deaths occur in these same women. A number of studies have found that elderly women are at increased risk for being diagnosed with advanced-stage breast cancer; nevertheless, it appears that elderly women do not have more poor prognostic factors that are associated with early relapse or short survival than younger women. Considering the fact that the population is aging and the increased incidence and mortality of breast cancer in the elderly, it is important to determine what can be done to reduce breast cancer mortality in the older segments of the population. Breast cancer screening with clinical breast exam and mammography, by leading to earlier diagnosis and therapy, improves the prognosis for survival. Nevertheless, data from the 1992 US National Health Interview Survey revealed that about 27% of women 65 and over had never even had a single mammogram. Of those who did have a mammogram, fewer than two-thirds had it within one year prior to the survey. The data for clinical breast exam were less discouraging, but nearly 20% of these women had never had an exam. From an ethical perspective, women in their mid-70s have an average of about 12 years of life remaining, and should be given every opportunity to live out these years in good health.

Delay in breast cancer: a review of the literature.

Delay in seeking medical attention for breast cancer symptoms, as well as delay in the diagnosing of and delivery of effective treatments for breast cancer may result in advanced states of disease, thereby contributing to breast cancer mortality. Our knowledge of the scope and characteristics of delay in breast cancer is limited. Delay can be divided into two components, patient and system delay. Patient delay is the time it takes for a women to seek help once she has discovered a breast symptom. System delay is the time it takes for a woman to be evaluated, diagnosed, and treated once she has sought help. Most of the studies have dealt with patient delay, with few studies being performed on system delay, especially in the United States. It is evident that patient and system delays of 2-3 months apiece do occur in a small percentage of cases. However, there is not a clear picture of the factors associated with these long delays. Studies have had conflicting results and have often been difficult to compare because of inconsistent definitions of delay. This review critically examines the available literature on delay in breast cancer. Given the lack of a complete understanding regarding the factors associated with long delay, and the fact that the earlier a breast cancer is diagnosed and treated, the greater the likelihood of long-term survival, it is especially important to do further work to determine the factors associated with long delay so that interventions can be designed to minimize delay and thus permit earlier diagnoses and treatments of breast cancers.

Breast cancer screening in older women.

BACKGROUND: There is currently an epidemic of breast cancer in women 65 years of age and older. The purposes of this paper are to explore the breast cancer screening behaviors of older women and to identify some of the determinants of screening in these women. METHODS: Data were analyzed from the 1987 National Health Interview Survey, a continuous nationwide household interview survey of the U.S. civilian, noninstitutionalized population. RESULTS: As in other studies, the utilization of breast cancer screening by older women was less in older women than in younger women. This was true for both mammography and clinical breast examination. A number of determinants of screening in older women were identified here. Women with a usual source of care and/or no activity limitation, as well as high school graduates, were the ones most likely to have received a screening mammogram and/or a screening clinical breast exam during the past year. DISCUSSION: The failure of older women to receive adequate breast cancer screening is an important concern which should be reevaluated, given the breast cancer epidemic in this population. This study identified a number of determinants of breast cancer screening in older women. For the most part, these determinants point to the primary care physician as the key to breast cancer screening in these women. Therefore, the primary care physician must be informed of, and encouraged to follow, the recommendations for periodic breast cancer screening in older women.

Breast cancer screening among older racial/ethnic minorities and whites: barriers to early detection.

Screening mammography for early detection of breast cancer has been shown to be an effective method for reducing mortality in older women. Based on the results from the 1987-88 National Health Interview Survey, older minority women have low prevalence rates of screening mammography. Among women aged 75 and older, 83.5% of Black women, 93.2% of Hispanic women, and 75.0% of White women have never had a mammogram. On the average, about 12% of minority women over the age of 65 have had a screening mammogram within the preceding year, compared with about 15% of White women. Among women 75 + years of age, Black and Hispanic women had markedly lower rates of clinical breast examination in the last year (23.4% and 20.5% respectively) as compared to White women (35.2%). The most common reason for not having a mammogram among Black women 65 years of age and older was that the doctor did not recommend a mammogram. For Hispanic and White women in this age group, the most common reason was that a mammogram was not needed or not necessary. Aggressive and creative breast cancer screening activities for minority aged 65 and older are clearly indicated.

The use of cohort vs repeated cross-sectional sample survey data in monitoring changing breast cancer screening practices.

BACKGROUND: The method used to select a study sample is a key element in designing a research protocol. This article explores two of the more common methods used, focusing on the relative advantages and disadvantages of each one. METHODS: Both cohort and repeated, independent cross-sectional surveys were conducted in each of 3 years (1988-1990) in the Awareness of Breast Cancer Screening Project to follow changing breast cancer screening rates among a population of women 50-75 years of age on Long Island, New York. RESULTS: Both survey methods revealed statistically significant increases in self-reports of mammography use. The cohort and repeated cross-sectional survey sample responses to questions concerning knowledge, attitudes, and behavior regarding breast cancer screening were comparable. An educational effect of the baseline survey itself on the cohort was not seen. CONCLUSIONS: Each of the two survey methods has advantages and disadvantages with respect to the other. The cohort method permits examination of changes in the same individual over time and is less costly and less time-consuming to perform. On the other hand, the cross-sectional method does not suffer from cumulative losses in respondents with repeated surveys and better reflects the changing community. The study findings can be used to guide the selection of an appropriate survey methodology for monitoring breast cancer screening practices in other settings.

Trends in mammography use and their relation to physician and other factors.

This study examines trends and factors (e.g., physician utilization) affecting mammography use from 1988 to 1990 among women residing in an area of high breast cancer incidence. Mail surveys of independent random samples of over 2000 women 50 to 75 years of age residing on Long Island were conducted each of the three study years, and responses were compared. Statistically significant increases in reported mammography use occurred over the 3-year period within all age, income, and educational subgroups. These were accompanied by a decline in reporting that the doctor did not recommend it, as a reason for not having a mammogram, and by a statistically significant increase in reported physician recommendation among those who visit a doctor annually, particularly those using a gynecologist. Clinical breast examination was the strongest predictor of mammography use, with knowledge of the recommended screening frequency also strong associated. Despite a regionally high incidence of breast cancer, screening mammography use corresponded to national rates. Access and visits to a regular physician were critical factors and substantiated the need for education of women, family practitioners, and internists about breast cancer screening guidelines.

Time to diagnosis and treatment of breast cancer: results from the National Breast and Cervical Cancer Early Detection Program, 1991-1995.

OBJECTIVES: This study examined times to diagnosis and treatment for medically underserved women screened for breast cancer. METHODS: Intervals from first positive screening test to diagnosis to initiation of treatment were determined for 1659 women 40 years and older diagnosed with breast cancer. RESULTS: Women with abnormal mammograms had shorter diagnostic intervals than women with abnormal clinical breast examinations and normal mammograms. Women with self-reported breast symptoms had shorter diagnostic intervals than asymptomatic women. Diagnostic intervals were less than 60 days in 78% of cases. Treatment intervals were generally 2 weeks or less. CONCLUSIONS: Most women diagnosed with breast cancer were followed up in a timely manner after screening. Further investigation is needed to identify and then address factors associated with longer diagnostic and treatment intervals to maximize the benefits of early detection.

Histology and smoking history of lung cancer cases and implications for prevention in Thailand.

BACKGROUND: Lung cancer is now a major public health problem in Thailand. This descriptive study looked at the issue of whether tumor histology varied with smoking status among lung cancer patients in Bangkok, Thailand. METHODS: A retrospective descriptive study was made of the 1,600 Thai patients with histologically proven lung cancer admitted to University of Siriraj Hospital between 1967 and 1991. Cigarette smoking histories were obtained, and histologies were classified and related to tobacco consumption. RESULTS: Overall, 78% were smokers, 72% being heavy smokers. The male to female ratio was 13:1 for smokers and 0.4:1 for nonsmokers. There were 29% squamous cell, 29% adenocarcinoma, 24% large cell, and 13% small cell carcinomas. Squamous cell carcinoma was significantly more frequent among cases with a history of smoking Thai cigarettes, which are known (from other studies) to be high in tar and nicotine, than among nonsmoking cases. Among the 350 nonsmokers, 252 of whom were female, adenocarcinoma was the most common (58%). CONCLUSIONS: The results suggest that Thai smokers can reduce their risk for lung cancer by quitting smoking, or by substituting lower tar brands. Antismoking programs should therefore be a public health priority. Given the prevalence of adenocarcinoma among nonsmokers, further work should be done to identify environmental causes.

Coding mammograms using the classification "probably benign finding--short interval follow-up suggested".

OBJECTIVE: Many benign breast lesions revealed by mammography show features indicating that the lesions have a high, but not complete, likelihood of being benign. The Breast Imaging Reporting and Data System (BI-RADS) allows radiologists to classify these mammograms as "probably benign finding-short interval follow-up suggested" (category 3). We explored whether certain factors are associated with the use of category 3 in a national cancer detection program. MATERIALS AND METHODS: We analyzed data from the National Breast and Cervical Cancer Early Detection Program, a comprehensive nationwide program that provides cancer screening for low-income and medically underserved women. The study population included all women at least 40 years old who had undergone mammography on or before September 30, 1996 (n = 372,760). RESULTS: Of the 372,760 mammograms, 7.7% were classified as category 3. The probability of receiving a category 3 classification decreased as patients' ages increased. Women who were symptomatic were nearly twice as likely as women who were asymptomatic to receive a category 3 classification, and women whose clinical breast examinations had abnormal findings were more than twice as likely as women with examinations having normal findings to receive a category 3 classification. The percentage of mammograms classified as category 3 by state or tribal organization ranged from 1.4% to 14.0%. CONCLUSION: Several patient variables, including patient symptomatology, were associated with the probability of having a mammogram classified as category 3. One of the most important determinants was where the patient underwent mammography, which suggests that variability exists among radiologists themselves in using this BI-RADS code for "probably benign" mammographic lesions.

Secondary prevention of cancer.

In recent years prevention has become extremely important in the war against cancer. For many cancers, major risk factors are not amenable to change and, therefore, secondary prevention through screening and early detection is the major type of intervention. Furthermore, with the discovery of cancer genes and tumor markers, which make it easier than ever before to identify people with increased risk of developing certain types of cancers, the role of secondary prevention has assumed an even greater value. This paper reviews recent advances in secondary prevention of those cancers for which overall efficacy of screening to reduce mortality has been demonstrated but for which some residual controversies exist: breast, cervical, and colorectal cancers.