Systemic Blood Predictors of Elevated Pulmonary Artery Pressure Assessed by Non-invasive Echocardiography After Acute Exposure to High Altitude: A Prospective Cohort Study

Aim

Elevated pulmonary artery pressure (ePAP) in response to high-altitude hypoxia is a critical physiopathological factor in the hypoxic adaptation that may lead to high-altitude pulmonary edema in the acute phase or high-altitude pulmonary hypertension in the long term. However, the sea-level predictors of risk factors for altitude-induced ePAP have not been examined. Thus, we aimed to identify the baseline systemic blood predictors of ePAP after acute high-altitude exposure.

Materials and Methods

A total of 154 participants were transported to a high altitude 3,700 m from sea level within 2 h. Echocardiography examinations were performed to assess the mean pulmonary artery pressure (mPAP) and hemodynamics at both altitudes. All the individuals underwent blood tests to determine the concentrations of vascular regulatory factors. Univariate and adjusted logistic regression analyses were performed to identify the independent predictors of ePAP and factors related to ePAP.

Results

The mPAP increased significantly from sea level to high altitude (19.79 ± 6.53–27.16 ± 7.16 mmHg, p < 0.05). Increased levels of endothelin (ET-1), Ang (1–7), Ang II, and bradykinin were found after high-altitude exposure, while the levels of nitric oxide (NO), prostaglandin E2 (PEG2), and serotonin decreased sharply (all p-values < 0.05). At high altitude, 52.6% of the subjects exhibited ePAP, and the mPAP was closely correlated with the baseline Ang II level (r = 0.170, p = 0.036) and follow-up levels of NO (r = −0.209, p = 0.009), Ang II (r = 0.246, p = 0.002), and Ang (1–7) (r = −0.222, p = 0.006) and the left atrial inner diameter (LAD, r = 0.270, p < 0.001). Both the baseline and follow-up NO and Ang II levels were significantly different between the ePAP and non-ePAP groups. Finally, we identified the baseline Ang II and NO concentrations as two independent predictors of ePAP (p < 0.05). We also found that two vascular regulatory factors with inverse roles, namely, Ang (1–7) and Ang II, at high altitudes were independently associated with ePAP. Additionally, ET-1, NO, PEG2, and LAD were associated with ePAP.

Conclusion

The baseline concentrations of Ang II and NO at sea level are two independent predictors of ePAP after acute high-altitude exposure. Furthermore, Ang (1-7) and Ang II combined with ET-1, NO, PEG2, and LAD at high altitudes may contribute to the development of ePAP.

[Risk factors of perivalvular leakage after transcatheter aortic valve replacement with Venus-A valve]

Objective: To investigate the risk factors of moderate or severe perivalvular leakage (PVL) after transcatheter aortic valve replacement (TAVR) with Veneus-A valve. Methods: This study was a single-center case-control study. The clinical data of patients with severe aortic stenosis, who underwent TAVR in the Department of Cardiology of Second Affiliated Hospital of Army Medical University from October 2017 to January 2021, were analyzed. According to the circumferential extent of prosthetic valve paravalvular regurgitation measured by transthoracic echocardiography before discharge (patients who died in hospital were referred to transesophageal echocardiography results after valve implanted), the patients were divided into moderate or severe PVL group and mild or non-PVL group. The clinical features, CT scan and analysis results of aortic root were compared between the two groups. Multivariate logistic regression analysis was used to identify the independent risk factors of postoperative moderate or severe PVL, and receiver operating characteristic (ROC) curve was used to explore the predictive value of related factors. Results: Eighty-two patients (mean age: (70.9±6.5) years, 46 males) were included in the analysis, there were 16 patients in the moderate or severe PVL group and 66 patients in the mild or non-PVL group. The proportion of male gender, depth of valve implantation, size of valve annulus and left ventricular outflow tract (LVOT), and coverage index of LVOT were significantly higher in moderate or severe PVL group than those in mild or non-PVL group (Pall<0.05). As there was a strong collinearity among the valve annular short diameter, LVOT short diameter and LVOT coverage index (partial correlation coefficient R 0.251-0.779, P<0.05), these parameters were not entered in regression model. Multivariate logistic regression analysis showed that valve implantation depth(OR=1.239,95%CI 1.036-1.442,P=0.023), aortic angulation(OR=1.128, 95%CI 1.044-1.312,P=0.038)and LVOT tract coverage index (OR=1.123, 95%CI1.003-1.315, P=0.032) were independent risk factors for moderate or severe PVL after TAVR. The ROC curve showed that the valve implantation depth could predict the occurrence of moderate or severe PVL after TAVR (area under ROC curve (AUC)=0.697, 95%CI 0.554-0.851, P=0.039). Conclusion: Among patients with severe aortic stenosis who undergo TAVR with Venus-A valve, the implantation depth, aortic angulation and LVOT coverage index are independent risk factors of moderate/severe PVL after TAVR, among which valve implantation depth could be used to predict the occurrence of moderate/severe PVL after TAVR.

Acute Mountain Sickness Is Associated With a High Ratio of Endogenous Testosterone to Estradiol After High-Altitude Exposure at 3,700 m in Young Chinese Men

Background: A large proportion of populations suffer from acute mountain sickness (AMS) after exposure at high altitude. AMS is closely related with age and gender implying that the sex hormones may play critical roles in AMS. Our observational study aimed to identify the association between the endogenous testosterone (T), estradiol (E2) and AMS. Methods: A total of 113 subjects were recruited in 2012. The participants were evaluated at 500 m and after acute (1 day) and short-term (7 days) high-altitude exposure at 3,700 m. The subjects also completed a case report form questionnaire and underwent blood pressure measurements and an echocardiography examination. The red blood cell (RBC) count, Hb concentration ([Hb]), hematocrit (HCT), E2, T, and erythropoietin (EPO) were measured. Results: Upon acute high-altitude exposure, E2 and EPO were significantly lower in AMS⁺ group, and T/E2 and stroke volume were higher. On the 1st day, AMS score correlated positively with the T/E2 ratio while it negatively correlated with E2. After 7 days at 3,700 m, the AMS⁺ subjects had higher erythropoietic parameters: EPO, T, and T/E2 were significantly higher in the AMS⁺ group. [Hb], RBC count, HCT, EPO, T and T/E2 were also correlated with AMS score. EPO, HCT, and the RBC count were also correlated with T/E2. Regression analyses indicated that T/E2 significantly correlated to AMS score and T/E2 on the 1st day was an independent predictor for AMS on the 7th day. Conclusion: AMS was correlated with T/E2 ratio and EPO. After short-term exposure, higher T/E2 may contribute to AMS together with EPO via erythropoiesis. Furthermore, T/E2 level at high altitude in the early stage was an independent predictor for AMS in the latter stage.

Physiological and psychological factors associated with onset of high-altitude headache in Chinese men upon acute high-altitude exposure at 3700 m

Aim

We aimed to identify clinical characteristics and risk factors associated with onset of high-altitude headache (HAH) after acute exposure at 3700 m.

Method

In two hours, 163 individuals ascended by plane to 3700 m. Demographic information, physiological and psychological measurements, cognitive function, physical work capacity tests and profile of mood states within one week prior to the departure and within 24 hours after arrival were examined.

Results

HAH patients featured significantly higher vertebral artery diastolic velocity (Vd), heart rate (HR) and pulmonary artery diameter. HAH was also associated with a more negative mood state, including scores for tension anxiety, depression, hostility, fatigue and confusion, as well as lower vigor (all p values <0.05). Furthermore, negative emotions were positively related to HAH severity. HAH slightly decreased cognitive functioning. HR, Vd, lack of vigor, confusion and self-reported anxiety (all p values <0.05) were independent risk factors for HAH. We have identified three independent baseline predictors for HAH including internal diameter of the left ventricle (LVD), Athens Insomnia Scale (AIS) and confusion score.

Conclusions

Higher HR, Vd, confusion and self-reported anxiety and insufficient vigor were independent risk factors for HAH. Furthermore, higher baseline LVD, AIS and confusion score are independent predictors of HAH.

Hemodynamic characteristics of high-altitude headache following acute high altitude exposure at 3700 m in young Chinese men

Background

This study aimed to identify the systemic and cerebral hemodynamic characteristics and their roles in high-altitude headache (HAH) among young Chinese men following acute exposure.

Methods

The subjects (n = 385) were recruited in June and July of 2012. They completed case report form questionnaires, as well as heart rate (HR), blood pressure, echocardiogram and transcranial Doppler examinations at 3700 m following a two-hour plane flight. A subgroup of 129 participants was examined at two altitudes (500 and 3700 m).

Results

HAH was characterized by increased HR and cardiac output (CO) and lower saturation pulse oxygen (SpO₂) (all p < 0.05). The change in tricuspid regurgitation was also different between the HAH positive (HAH+) and HAH negative (HAH-) subjects. Furthermore, the HAH+ subjects exhibited faster mean (V_m), systolic (V_s) and diastolic (V_d) velocities in the basilar artery (BA; all p < 0.05) and a faster V_d ( 25.96 ± 4.97 cm/s vs. 24.76 ± 4.76 cm/s, p = 0.045) in the left vertebral artery (VA). The bilateral VA asymmetry was also significantly different between the two groups. The pulsatility index (PI) and resistance index (RI) of left VA were lower in the HAH subjects (p < 0.05) and were negatively correlated with HAH (p < 0.05). Baseline CO and V_m in left VA (or right MCA in different regressions) were independent predictors for HAH, whereas CO/HR and ΔV_d (V_d difference between bilateral VAs) were independent risk factors for HAH at 3700 m.

Conclusions

HAH was characterized, in part, by increased systemic hemodynamics and posterior cerebral circulation, which was reflected by the BA and left VA velocities, and lower arterial resistance and compliance. Furthermore, baseline CO and V_m in left VA or right MCA at sea level were independent predictors for HAH, whilst bilateral VA asymmetry may contribute to the development of HAH at high altitude.

Electronic supplementary material

The online version of this article (doi:10.1186/s10194-015-0527-3) contains supplementary material, which is available to authorized users.

Analysis of human papilloma virus in oral squamous cell carcinoma using p16: An immunohistochemical study

Aims:

The aim of this study is to evaluate the expression of human papilloma virus (HPV) in oral squamous cell carcinoma (OSCC) and to correlate the association of HPV in histological grades of OSCC using p16 (p16INK4a) immunohistochemistry (IHC).

Subjects and Methods:

This study consists of 30 histological diagnosed cases of OSCC (10-well-differentiated oral squamous cell carcinoma [WDOSCC], 10-moderately differentiated oral squamous cell carcinoma [MDOSCC] and 10-poorly differentiated oral squamous cell carcinoma [PDOSCC]). The sections were subjected to IHC procedure using p16. Two parameters in immunohistochemical p16 expression were evaluated by 3 observers based on the criteria by Galgano M. Tetal (2010) (a) percentage of p16 positive cases (b) pattern of p16 staining in various grades of OSCC.

Statistical Analysis Used:

Kappa test.

Results:

Totally, 30 samples of 0SCC, p16 positivity was noted in 26/30 (86.66%). Of 26 positive cases, p16 staining was positive in 7/10 (70%) of WDOSCC, 9/10 (90%) in MDOSCC and, 10/10 (100%) PDOSCC. Incidentally, we also found single dispersed cell staining in WDOSCC, patchy staining in MDOSCC and more diffuse staining pattern predominant in PDOSCC.

Conclusions:

Our study revealed an association between HPV and OSCC. Diffuse staining pattern was noted in PDOSCC, which in turn depicts the increase viral overload, which might have an influence on its aggressive behavior.

Insulin resistance and bariatric surgery

The objective of this article is to systematically review the changes in insulin resistance after various types of bariatric surgical procedures. A Pubmed and EMBASE search for studies measuring insulin resistance before and after bariatric surgery was done and all original research articles from 1980 to present (2011) were included. Only the currently widely performed bariatric procedures were included. A meta-analysis of change in HOMA-IR was conducted, grouping studies with similar duration of follow-up. The percentage decrease in HOMA-IR at <=2 weeks, 1 month, 3 months, 6 months, 12 months and >16-18 months was found to be (mean ± standard error) -33.48 ± 5.78, -46.43 ± 6.99, -38.79 ± 9.64, -58.62 ± 7.38, -44.91 ± 7.98 and -67.04 ± 10.78%, respectively. RYGB (gastric bypass) and BPD (biliopancreatic diversion) produced a significant decrease in insulin resistance at 2 weeks after surgery, while LSG (sleeve gastrectomy) was strongly trending. LSG produced an earlier decrease in insulin resistance when compared to LAGB (gastric banding). RYGB, BPD and LSG produce an early decrease in insulin resistance through yet unknown mechanisms.

CHL1 cooperates with PAK1-3 to regulate morphological differentiation of embryonic cortical neurons

The cell adhesion molecule close homologue of L1 (CHL1) is important for apical dendritic projection and laminar positioning of pyramidal neurons in caudal regions of the cerebral cortex. The p21-activated kinase (PAK1-3) subfamily of serine/threonine kinases has also been implicated in regulating cell adhesion, migration, and morphology. Immunofluorescence staining in mouse embryonic brain showed that PAK1-3 was expressed in embryonic cortex and colocalized with CHL1 during neuronal migration and differentiation. To investigate a cooperative function for CHL1 and PAK in pyramidal cell differentiation or migration, a dominant-negative PAK mutant (PAK1 AID) that inhibits PAK1-3 kinase activity while coexpressing a green fluorescent protein (GFP) reporter was electroporated into the lateral ventricles of wild type (WT) and CHL1 null mutant mouse embryos (E14.5), then brain slices were cultured and neurons analyzed for laminar positioning and morphology by confocal microscopy after 3 days in vitro. Expression of PAK1 AID in CHL1 mutant cortex inactivated PAK and caused embryonic cortical neurons to branch profusely in the intermediate zone (IZ) and cortical plate (CP). The number of nodes, terminals and length of leading processes/apical dendrites of CHL1 mutant embryos expressing PAK1 AID increased dramatically, compared to CHL1 mutants without PAK1 AID, or WT embryos with or without PAK1 AID. These findings suggest that CHL1 and PAK1-3 kinase cooperate, most likely in independent pathways, in regulating morphological development of the leading process/apical dendrite of embryonic cortical neurons.

Role of different cytokines and seizure susceptibility: a new dimension towards epilepsy research

Epilepsy is a common health problem. Although variety of factors influence the incidence and prevalence of seizures, cytokines are considered to play an important role in seizures. Cytokines are also known to be involved in other neurodegenerative disorders. Proinflammatory cytokines like IL-1, IL-6, TNF-alpha and growth factor vascular endothelial growth factor (VEGF) as well as anti-inflammatory cytokine IL-10 and related molecules have been described in CNS and plasma of experimental models of seizures and clinical cases of epilepsy. There are reports suggesting more predispositions to seizures during inflammatory conditions like colitis, pneumonia and rheumatoid arthritis. These inflammatory cytokines and growth factors are also known to have dual roles in affecting seizure susceptibility. It remains to be seen if cytokine modulators can be therapeutically exploited for patients with inflammatory disorder and suffering from epilepsy.

Experimentally induced various inflammatory models and seizure: understanding the role of cytokine in rat

BACKGROUND

The mechanism of epileptogenesis is not well established. There is higher incidence of seizures among patients with chronic inflammatory disease. Cytokines are rapidly induced in the brain after a variety of stimuli including inflammation. Aim of this study was to produce various inflammatory models and seizure to understand the role of TNFalpha in above mentioned models.

MATERIALS AND METHODS

A total of 54 male rats were included in the study. Animals were divided into 3 groups of colitis, arthritis, and cotton wool granuloma. Each group had 3 subgroups of control, model and treatment. At the end of 3 days in colitis, 17 days in arthritis and 7 days in cotton wool granuloma groups a subconvulsive dose of PTZ (40 mg/kg i.p) was injected to note seizure onset and seizure score. Brain samples were subjected to DNA fragmentation testing. Presence of inflammation was confirmed by morphology and histology. Plasma and brain TNFalpha levels were measured.

RESULTS

The models of colitis, arthritis and CWG were effectively produced as evidenced by morphology and histology scores (p<0.001). Seizure onset was reduced and grade was increased (p<0.001). Thalidomide reduced the morphological, histological (p<0.002), DNA fragmentation and seizure grade (p<0.001) while increased seizure onset (p<0.001) in the arthritis group. TNFalpha levels in both plasma and brain were reduced following thalidomide treatment (p<0.002) in arthritis group. There were no significant findings in colitis or cotton wool granuloma groups.

CONCLUSION

Inflammation was associated with decreased threshold to PTZ induced seizure. Thalidomide is effective in reducing the extent of arthritis as well as reducing the seizure scoring and increasing seizure onset in the adjuvant arthritis group. Thalidomide was also effective in reducing TNFalpha levels thus contributing to its antiepileptic activity.

Isolation and characterization of ethanol-producing yeasts from fruits and tree barks

AIMS

Isolation and identification of yeasts converting xylose to ethanol.

METHODS AND RESULTS

A total of 374 yeasts were isolated from a variety of rotten fruits and barks of trees. Out of these, 27 yeast strains were able to assimilate xylose and produce 0.12-0.38 g of ethanol per gram of xylose. Based on phylogenetic analysis of D1/D2 domain sequence of LSU (Large Subunit) rRNA gene and phenotypic characteristics the ethanol-producing strains were identified as member(s) of the genera Pichia, Candida, Kluyveromyces, Issatchenkia, Zygosacchraomyces, Clavispora, Debaryomyces, Metschnikowia, Rhodotorula and Cryptococcus.

CONCLUSION

Yeast strains producing ethanol from xylose have been isolated from a variety of rotten fruits and barks of trees and identified.

SIGNIFICANCE AND IMPACT OF THE STUDY

Environmental isolates of yeasts which could convert xylose to ethanol could form the basis for bio-fuel production and proper utilization of xylan rich agricultural and forest wastes.

Electronic topological and structural transitions in AuGa(2) under pressure

Results of electronic band structure calculations, electrical resistance, thermoelectric power (TEP), and x-ray diffraction measurements, under pressure carried out on AuGa(2) to investigate its anomalous behaviour are reported. The first principles electronic band structure calculations confirm that a flat band close to the Fermi level along the Γ-X direction of the Brillouin zone is responsible for the unusual behaviour of AuGa(2). In synchrotron-based high-pressure x-ray diffraction measurements, it is observed to undergo a structural phase transition above 7 GPa. The TEP variation with pressure and the P-V data up to 7 GPa transformed to the universal equation of state (UEOS) indicate the existence of an electronic topological transition (ETT) near 3.2 GPa. Consistent with this, in electronic structure calculations carried out at reduced sample volume corresponding to 4 GPa, it is seen that the flat band crosses the Fermi level. The structure above 7 GPa is a distortion of the CaF(2) phase. This structure continuously evolves with increasing pressure. The continuous variation of electrical resistance across the transition is consistent with this.

High-pressure study of adamantane: variable shape simulations up to 26 GPa

We report simulations of adamantane by carefully combining ab initio and empirical approaches to enable simulations with internal degrees of freedom on crystalline adamantane up to a pressure of 26 GPa. Two sets of simulations, assuming the adamantane molecule as a rigid (RB) and flexible body (FB), have been carried out as a function of pressure up to 26 GPa to understand changes in the crystal structure as well as molecular structure. The flexible body simulations have been performed by including 6 lowest frequency internal modes (obtained from DFT calculations performed with Gaussian98) out of the total of 72. The calculated variation in c/a and V/V(0) from the RB and FB calculations as a function of pressure have been compared with the experimental curve. Other relevant thermodynamic and structural properties reported are the radial distribution functions, deviation in the position of a given type of atom with respect to its position at standard pressure, delta(s), cell parameters, volume, and energy. With an increase in pressure, three additional peaks are seen to develop gradually at three different pressures in the center of mass (com)-com radial distribution function (rdf). We attribute these changes to structural transformations (probably second-order phase transitions) which is consistent with the three phase transitions reported by Vijayakumar et al. for adamantane in the pressure range of 1 atm-15 GPa. Our simulations also show that these additional peaks in the rdf's are associated with the differences between opposite and parallel spin neighbors of Greig and Pawley as well as the crystallographic directional dependence of intermolecular distances in the first three shells of the neighbors. Also, the structural quantities from the RB calculation show considerable deviation from the FB calculation for pressures greater than 5 GPa, which suggests that the rigid body assumption for molecules may not be valid above this pressure.

Changed clinical aspects of primary liver cancer in China during the past 30 years

BACKGROUND

Primary liver cancer (PLC) is one of the most frequently seen tumors in China. Thirty years ago, patients with PLC were often detected at relatively late stage, with a palpable mass or marked clinical symptoms and poor prognosis. In the past 30 years, the diagnosis and treatment of PLC have been greatly improved with better prognosis.

METHODS

In order to study the changes of PLC during the 30 years, the clinical data of 3250 patients with PLC from 10 medical institutions of China were collected, analyzed, and compared with those of 3254 PLC patients before the 30 years.

RESULTS

In the 3250 patients aged 1-80 years, with an average age of 49.1 years, the male to female ratio (2.3:1) was lower than that before the 30 years. 73.5% of the 3250 patients sought medical advice within 3 months after the onset of the disease in contrast to 63.8% before the 30 years. Compared with those patients before the 30 years the symptoms and signs were alleviated generally. The HBsAg positive rate was 81.0%, but the HCV-Ab positive rate was 13.2%. The AFP level in 75% of patients was elevated, but in the remaining 25% was normal. 1912 patients (58.8%) were confirmed pathologically. Among them 1755 patients (91.8%) had hepatocellular carcinoma. The overall resection rate was 46.3%. Those who had early, middle, late stage carcinoma accounted for 29.9%, 51.5%, and 18.6% respectively in contrast to 0.4%, 47.0%, and 52.6% reported before the 30 years. The 1-, 3-, 5-year survival rates of the patients were 66.1%, 39.7%, and 32.5% respectively, whereas 93.5%, 70.1%, and 59.1% for the early stage patients, and 65.3%, 30.5%, and 23.5% for the middle stage patients. The half and 1-year survival rates of the late stage patients were 52.5%, and 14.7%, respectively.

CONCLUSION

Comparison with the clinical data before and after the 30 years show that PLC can be diagnosed early. More PLC patients tend to undergo resection while receiving a better conservative treatment, which ensures a prognosis.

Evidence-based protocols for the management of well-differentiated carcinomas of the thyroid

OBJECTIVES

In recent years, well-differentiated carcinomas of the thyroid have been stratified into low-risk and high-risk groups. The pattern of thyroid cancer in India is different from that seen in the West. Moreover, patients present with more advanced stages of the disease. Our aim was to develop protocols for the management of well-differentiated thyroid cancer, based on the analysis of our data and our experience.

METHODS

Cases of thyroid carcinoma, which were surgically treated at the Tata Memorial Hospital during 1970-5, were studied. The survival curves were plotted according to the Kaplan-Meier method. Univariate analysis was done using the log rank test. The prognostic factors analyzed were age, sex, tumour size, extra-thyroid extension, distant metastases and lymph node metastases. Multivariate analysis using the Cox regression model was performed. Analyses were separate for follicular and papillary carcinomas.

RESULTS

Four hundred and seventeen cases were entered in the study, of which 198 were follicular and 219 were papillary. Based on the evidence derived from this study, we stratified our cases into low- and high-risk groups. The low-risk group consisted of patients below 40 years of age, nodules smaller than 5 cm, absence of extra-thyroidal spread and absence of distant metastases. For follicular carcinoma, the low-risk group had 100% survival at 15 years, compared with 40% for the high-risk group. (p < 0.001). For papillary carcinomas, the survival at 15 years was 95% for the low-risk group and 40% for the high-risk group (p < 0.001).

CONCLUSIONS

We recommend lobectomy for the low-risk group, and total thyroidectomy for the high-risk group and for cases with lymph node metastases. In the latter, total thyroidectomy facilitates the use of 131I.

Infertility among women exposed prenatally to diethylstilbestrol

Although it is well established that women exposed to diethylstilbestrol in utero have an increased risk of spontaneous abortion, ectopic pregnancy, and preterm delivery, it is not known whether they also have an increased risk of infertility. The authors assessed this question in data from a collaborative follow-up study of the offspring of women who took diethylstilbestrol during pregnancy. In 1994, 1,753 diethylstilbestrol-exposed and 1,050 unexposed women from an ongoing cohort study (National Cooperative Diethylstilbestrol Adenosis Study and Dieckmann cohorts) provided data on difficulties in conceiving and reasons for the difficulty. Age-adjusted relative risks were computed for the association of diethylstilbestrol exposure with specific types of infertility. A greater proportion of exposed than unexposed women were nulligravid (relative risk (RR) = 1.3, 95% confidence interval (CI): 1.1, 1.5), and a greater proportion had tried to become pregnant for at least 12 months without success (RR = 1.8, 95% CI: 1.6, 2.1). Diethylstilbestrol exposure was significantly associated with infertility due to uterine and tubal problems, with relative risks of 7.7 (95% CI: 2.3, 25) and 2.4 (95% CI: 1.2, 4.6), respectively. The present findings indicate that diethylstilbestrol-exposed women have a higher risk of infertility than do unexposed women and that the increased risk of infertility is primarily due to uterine or tubal problems.

Height and breast cancer risk: results from the Black Women's Health Study (United States)

OBJECTIVES

Numerous studies, but not all, have yielded positive associations between adult height and risk of breast cancer. There are few data on black women. We evaluated adult height in relation to breast cancer in data from the Black Women's Health Study, a prospective cohort study of 64,530 African-American women aged 18-69 years at baseline in 1995.

METHODS

A total of 910 cases of breast cancer were analyzed: 700 prevalent cases reported at baseline and 210 incident cases that occurred during the first 2 years of follow-up. A comparison group of controls frequency-matched on 5-year category of birth year was chosen from among participants who had not developed breast cancer. Odds ratios (OR) were calculated for various categories of adult height compared to a reference category of height less than or equal to 61 inches (155 cm), with control for current age, age at menarche, and years of education.

RESULTS

Increased height was associated with an increased risk of breast cancer overall (p trend = 0.001); the OR for the highest category of height, > 69 inches (175 cm), was 1.6 (95% confidence interval 1.1-2.3). The association was stronger among premenopausal women and women who had less than 16 years of education. Results were similar for prevalent and incident cases.

CONCLUSION

The present findings indicate that height is associated with breast cancer risk in African-American women.

Low-dose oral contraceptive use and the risk of myocardial infarction

BACKGROUND

Studies of oral contraceptives (OCs) containing 50 microg or more of estrogen suggest an increased risk of myocardial infarction (MI) among current users, particularly if they smoke heavily.

OBJECTIVE

To assess whether use of the newer lower-dose OCs increases the risk of MI.

METHODS

A case-control study was conducted from January 1985 through March 1999 in 75 hospitals in the greater-Boston and greater-Philadelphia areas. Data on OC use and MI risk factors were obtained by interview from 627 women with a nonfatal first MI (cases) and 2947 female hospital controls younger than 45 years.

RESULTS

The overall odds ratio (OR) for current OC use relative to never used was 1.3 (95% confidence interval [CI], 0.8-2. 2). The OR was elevated, 2.5 (95% CI, 0.9-7.5), among heavy smokers (>/=25 cigarettes per day) but close to 1.0 among lighter smokers (OR = 0.8) and nonsmokers (OR = 1.3). For current OC use together with heavy smoking relative to nonuse and nonsmoking, the OR was 32 (95 % CI, 12-81), considerably greater than that for heavy smoking alone, 12 (95% CI, 8.6-16). The ORs did not vary according to the type of formulation or the dose of estrogen; there were too few users to assess the new 20-microg preparations. Past OC use was unrelated to risk.

CONCLUSION

Current use of low-dose OCs in the United States is unrelated to an increased risk of MI among nonsmokers and light smokers, but users who smoke heavily may be at greatly increased risk.

Evaluation of Lp[a] and other independent risk factors for CHD in Asian Indians and their USA counterparts

Conventional risk factors for coronary heart disease (CHD) do not completely account for the observed increase in premature CHD in people from the Indian subcontinent or for Asian Indians who have immigrated to the USA. The objective of this study was to determine the effect of immigration to the USA on plasma levels of lipoprotein [a] (Lp[a]) and other independent risk factors for CHD in Asian Indians. Three subject groups were studied: group 1, 57 subjects living in India and diagnosed with CHD (CHD patients); group 2, 46 subjects living in India and showing no symptoms of CHD (control subjects); group 3, 206 Asian Indians living in the USA. Fasting blood samples were drawn to determine plasma levels of triglyceride (TG), total cholesterol (TC), low density lipoprotein [LDL cholesterol (LDL-Chol)], high density lipoprotein [HDL cholesterol (HDL-Chol)], apolipoprotein B-100 (apoB-100), and Lp[a]. Apolipoprotein [a] (apo[a]) size polymorphism was determined by immunoblotting. Plasma TG, apoB-100, and Lp[a] concentrations were higher in CHD patients than in control and USA groups. CHD patients had higher levels of TC and LDL-Chol and lower HDL-Chol than control subjects. However, the USA population had higher levels of TC, LDL-Chol, and apoB-100 and lower HDL-Chol than control subjects. Plasma Lp[a] levels were inversely correlated with the relative molecular weight of the more abundant of each subject's two apo[a] isoforms (MAI), and CHD patients showed higher frequencies of lower relative molecular weights among MAI. Our observed changes in lipid profiles suggest that immigrating to the USA may place Asian Indians at increased risk for CHD. This study suggests that elevated plasma Lp[a] confers genetic predisposition to CHD in Asian Indians, and nutritional and environmental factors further increase the risk of CHD. This is the first report implicating MAI size as a predictor for development of premature CHD in Asian Indians. Including plasma Lp[a] concentration and apo[a] phenotype in screening procedures may permit early detection and preventive treatment of CHD in this population.

Survey for tuberculosis in a tribal population in North Arcot District

SETTING

Tribal villages in the jungles of the Jawadhu hills, South India.

OBJECTIVE

To estimate the prevalence of tuberculosis (TB) infection and disease in a remote tribal population.

DESIGN

A cross-sectional survey with two-stage screening for identification of cases. A stratified probability proportional sample with the hamlet as the unit.

METHODS

Among 56 revenue divisions with a population of about 66,000, 24 revenue divisions were selected. Among 26,320 persons registered, children < 10 years were tuberculin tested and reactions were read after 72 hours. Those over 15 were X-rayed, and tuberculosis symptoms were investigated. Sputum was collected from those with abnormal X-ray or symptoms and examined for smear and culture positivity and sensitivity.

RESULTS

Of the 6952 children tested and read, 5% had BCG scars and the prevalence of infection was 5%. The annual risk of infection was 1.1. Among adults, the prevalence of bacillary cases was 8/1000 and X-ray cases 29/1000. The prevalence of bacillary disease was higher among males, particularly with increasing age. Thirty symptomatic cases had normal X-rays and 63 X-ray cases had no symptoms. Thus prevalence would have been underestimated if either method had been used alone for screening. Isoniazid resistance was seen in 12% of patients, two of whom also had rifampicin resistance (2.6%).

CONCLUSIONS

The prevalence and pattern of tuberculosis in this tribal group is similar to that observed in non-tribal areas.

Comparison of alternative survey methods for sensitive self-reported behaviours in a follow-up study of isotretinoin

BACKGROUND

Responses to questions on sensitive behaviours can be affected by when and how questions are asked.

METHODS

Using data from an ongoing survey of women taking isotretinoin (a teratogenic drug used to treat acne), we compared answers to questions on contraceptive use during therapy among 126966 women who had begun treatment in 1990-93. 20503 were randomly assigned to a group which was surveyed by telephone at the start of treatment, during treatment and 6 months after treatment ended (DAT group). 106463 received a mail survey 6 months after treatment ended (AT group). Women who could not be contacted during treatment, along with the non-respondents in the AT group, received follow-up surveys by US mail, air courier and, if necessary, were called by telephone.

RESULTS

The response rate was higher in the DAT group (96.4%) than in the AT group (84.8%). Among respondents, the odds of reported contraceptive use in the AT group compared with the DAT group (asked at 6 months after treatment) was 1.41 [95% confidence interval (CI): 1.36-1.46]. However, rates of oral contraceptive (OC) use were virtually identical in the two groups. In both groups, women surveyed by telephone reported lower rates of contraceptive use than women surveyed by mail. In the AT group, a late response was associated with a significantly lower rate of contraceptive use.

CONCLUSIONS

Both mode of data collection (phone versus mail) and time to response affected reported rates of contraceptive use. Reasonable assumptions about the effect of non-response could not account for the difference between the AT and DAT groups. We found that contacting women during their treatment did not increase their reported use of contraceptives.

Strenuous physical activity and breast cancer risk in African-American women

OBJECTIVES

Some studies of white women suggest that exercise reduces the incidence of breast cancer. There are no data on black women. We assessed the relationship between strenuous physical activity and prevalent breast cancer among participants in the Black Women's Health Study.

METHODS

Data on strenuous recreational physical activity at various ages and other factors were collected in 1995 by mail questionnaire from 64,524 United States black women aged 21 to 69 years. The 704 women who reported breast cancer (cases) were matched on age and on menopausal status at the time of the breast cancer diagnosis with 1408 women who did not report breast cancer (controls). Odds ratios for levels of physical activity at various ages were derived from conditional logistic regression with control for potential confounding factors.

RESULTS

Odds ratios for > or =7 h per week relative to < 1 were significantly reduced for strenuous activity at age 21 for breast cancer overall and premenopausal breast cancer, at age 30 for breast cancer overall, and at age 40 for postmenopausal breast cancer. There was no evidence of a reduction associated with exercise in high school.

CONCLUSIONS

The findings of the present study suggest that strenuous physical activity in early adulthood is associated with a reduced risk of breast cancer in African-American women.

A case-control study of analgesic use and ovarian cancer

A recent case-control study raised the hypothesis that acetaminophen use 1 day or more per week for at least 6 months reduces the risk of epithelial ovarian cancer. We assessed analgesic use in relation to epithelial ovarian cancer risk using data from our case-control surveillance study of medication use and cancer. Patients were interviewed in hospitals in Baltimore, Boston, New York, and Philadelphia during 1976-1998. We compared 780 women with epithelial ovarian cancer to 2053 cancer controls and 2570 noncancer controls. For acetaminophen use 1 day or more per week for at least 6 months, the odds ratio estimate was 0.9 (95% confidence interval, 0.6-1.4) derived with cancer controls and 1.0 (0.6-1.5) with noncancer controls. Estimates for more frequent and longer term use were also compatible with 1.0. The odds ratios among patients with metastatic ovarian cancer were reduced but not statistically significant. The odds ratio for use of nonsteroidal anti-inflammatory drugs 4 or more days per week for at least 5 years, 0.5, was statistically significant. The present results provide only weak support for a reduction in the risk of epithelial ovarian cancer among acetaminophen users. They raise the possibility of an inverse association with long-term nonsteroidal anti-inflammatory drug use.

Evaluation of an isometric and a position joystick in a target acquisition task for individuals with cerebral palsy

Individuals with cerebral palsy (CP) with upper limb disability have difficulty operating standard computer input devices such as, a mouse and a keyboard. The present study evaluated the performance of unimpaired individuals and those with CP in the use of a zero-order spring-centered position joystick and a zero-order isometric joystick when interacting with the computer. We hypothesize that the isometric device due to its stiff resistance would provide better control on cursor movement than the position joystick. The subjects acquired differently sized targets at different distances by positioning a cursor on the target. Performance with the position joystick was superior to that of the isometric joystick. The time to acquire the target was directly proportional to the cursor-target distance A, and indirectly proportional to the target size W. Subjects chose to move more slowly toward the smaller and closer targets and they increased speed for larger and more distant targets. The phase-plane diagram that plots values of the velocity profile of the cursor over its displacement revealed the presence of one large amplitude movement that accounts for the peak velocity of the cursor, and several submovements. Fitts' index of difficulty, log(e)(2W/A) was found to be a good predictor of the movement time in a cursor positioning task for both, unimpaired individuals and those with CP.

Hemangiopericytoma of greater omentum

A 67-year-old man presented with a painless abdominal lump. CT scan revealed a large vascular intraperitoneal mass. At laparotomy, a large, vascular tumor was seen to arise from the greater omentum, which was resected. At histology, this tumor was a benign hemangiopericytoma.

Descriptive epidemiology of physical activity in African-American women

OBJECTIVES

We assessed walking for exercise and moderate and strenuous physical activity in relation to both demographic and health-related characteristics among African-American women from various parts of the United States who participate in the Black Women's Health Study.

METHODS

The data were collected in 1995 by mail questionnaire from 64,524 U.S. black women aged 21 to 69 years. The 64,101 women who provided data on physical activity are the subjects of the present report.

RESULTS

The present study revealed low levels of physical activity among the African-American women: 57% reported an hour or less per week walking for exercise, 18% reported moderate activity, and 61% reported strenuous physical activity. Strenuous physical activity increased with education. Higher levels of walking for exercise and moderate and strenuous activity were associated with higher levels of participation in strenuous exercise in high school.

CONCLUSION

Physical activity levels are low in African-American women. Based on the findings of the present study it may be suggested that educational efforts to increase levels of physical activity should start at an early age.

Socio-demographic and maternal determinants of low birth weight: a multivariate approach

A community based study was conducted in the rural areas of Udupi taluk, Karnataka state of South India to identify the socio-demographic, maternal and obstetric determinants of low birth weight. All singleton live births that occurred in the study area during a one year period (October 1991 to September 1992) were included. A total of 2919 singleton child-mother pairs formed the basis of the analysis. Information about social, demographic and economic conditions of the families; maternal factors such as age, parity, quality of antenatal care and previous obstetric history were collected by interviewing the mothers and family members and verifying the available medical records through the field investigators especially recruited and trained for this purpose. Data was analyzed using multiple logistic regression model. Primis, elderly mothers and mothers who had not received good quality antenatal care were found to be more at risk of having low birth weight babies. Other significant determinants were family custom, socio-economic status and environmental sanitation.

Correlates of hysterectomy among African-American women

Hysterectomy is the second most common surgery performed on US women. Baseline data from a large study of African-American women were used to examine correlates of premenopausal hysterectomy. Analyses were conducted on participants aged 30-49 years; 5,163 had had a hysterectomy and 29,787 were still menstruating. Multiple logistic regression was used to compute prevalence odds ratios for the association of hysterectomy with various factors. Hysterectomy was associated with region of residence: Odds ratios for living in the South, Midwest, and West relative to the Northeast were 2.63 (95% confidence interval (CI): 2.38, 2.91), 2.02 (95% CI: 1.81, 2.25), and 1.89 (95% CI: 1.68, 2.12), respectively. Hysterectomy was inversely associated with years of education and age at first birth: Odds ratios were 1.96 (95% CI: 1.74, 2.21) for < or =12 years of education relative to >16 years and 4.33 (95% CI: 3.60, 5.22) for first birth before age 20 relative to age 30 or older. Differences in the prevalence of major indications for hysterectomy did not explain the associations. This study indicates that the correlates of hysterectomy among African-American women are similar to those for White US women. The associations with geographic region and educational attainment suggest that there may be modifiable factors which could lead to reduced hysterectomy rates.

Risk factors for coronary heart disease in African American women

There have been few studies of risk factors for coronary heart disease in African American women. The authors investigated factors associated with prevalent coronary heart disease in data provided by participants in the Black Women's Health Study. In 1995, 64,530 US Black women aged 21-69 years completed postal health questionnaires. The 352 women who reported having had a heart attack (cases) were frequency matched 5:1 on age with 1,760 women who had not (controls); medical record review for 35 cases indicated that two-thirds had had a heart attack and the remainder had other coronary heart disease. Odds ratios, obtained from multiple logistic regression analyses, were significantly elevated for cigarette smoking, drug-treated hypertension, drug-treated diabetes mellitus, elevated cholesterol level, and history of heart attack in a parent. High body mass index (kg/m2) was associated with coronary heart disease in the absence of control for hypertension, diabetes mellitus, and elevated cholesterol but not when they were controlled, suggesting that obesity may influence risk as a result of its effects on blood pressure, glucose tolerance, and cholesterol levels. Odds ratios increased with increasing parity and with decreasing age at first birth. These data suggest that important risk factors for coronary heart disease are similar in Black women and White women.

Risk of breast cancer according to use of antidepressants, phenothiazines, and antihistamines

In laboratory studies, some antidepressants caused increased growth of mammary tumors. The relation of use of these drugs to the development of breast cancer was examined in a hospital-based case-control study. Information, including lifetime medication history, was collected by interview from 5,814 women with primary breast cancer diagnosed within the previous year, 5,095 women with primary malignancies of other sites, and 5,814 women with other conditions. Relative risks were estimated by using unconditional multiple logistic regression for regular use (> or =4 days per week for > or =4 weeks beginning > or =1 year before admission) of antidepressants and structurally similar drugs. With reference to never use of each drug, relative risks were statistically compatible with 1.0 for selective serotonin reuptake inhibitors (SSRI), tricyclics, other antidepressants, phenothiazines, and antihistamines; results were very similar using both control groups. There were no significant increases in risk for any category of regular use, stratified according to cumulative duration of use or time interval since the most recent use or for any individual drug within the broader classes. However, the estimate for regular SSRI use in the previous year, 1.8, was of borderline statistical significance (95% confidence interval: 1.0, 3.3). The findings do not support an overall association between the use of antidepressants, phenothiazines, or antihistamines and breast cancer. However, the results for SSRIs are not entirely reassuring.

Knowledge of and attitudes to HIV/AIDS of senior secondary school pupils and trainee teachers in Udupi District, Karnataka, India

A cross-sectional descriptive study using a questionnaire with mostly closed-ended questions was carried out on 990 pupils and 46 trainee teachers to investigate their knowledge of and attitudes to HIV/AIDS. Pupils in one school were reassessed after a health talk and distribution of a handout. Despite having had no formal sex education, most respondents were reasonably well informed about the transmission of HIV. However, there were many misconceptions about transmission and prevention and 16.9% of pupils were found to possess very little knowledge of HIV/AIDS. Mass media, teachers and health workers were quoted as the main sources of knowledge. It was found that 24.3% pupils and 6.3% of trainee teachers thought there was a cure, and 27.4% of pupils and 14% of trainee teachers thought there was a vaccine to prevent HIV infection. Schools that were rural, private and English-speaking scored better, as did male students and schools teaching science. The necessity of formal sex education was expressed by 98.5% of pupils and all the trainee teachers. The pupils who were reassessed after receiving a talk and handout showed significant improvement in their knowledge and a change in attitude (p < 0.01). The mass media are important in disseminating knowledge on HIV/AIDS in India but due to the lack of inter-personal approaches to the education system, knowledge is inadequate and misconceptions exist.

Oral contraceptive use and risk of gestational trophoblastic tumors

BACKGROUND

Gestational trophoblastic disease refers to a spectrum of rare benign and malignant gynecologic disorders whose pathogenesis is not well understood. Recent studies from China and the United States have raised the hypothesis that long-term use of oral contraceptives before conception may increase the risk of gestational trophoblastic tumors. A multicenter case-control study of gestational trophoblastic tumors was undertaken to test this hypothesis.

METHODS

Telephone interviews were conducted with 235 case patients, including 50 with gestational choriocarcinoma, and 413 control subjects matched on recentness of pregnancy, age at pregnancy, and area of residence. Relative risks (odds ratios) were computed by conditional logistic regression. Reported P values are two-sided.

RESULTS

The relative risk estimate for ever having used oral contraceptives before the index pregnancy was 1.9 (95% confidence interval [CI] = 1.2-3.0), and the risk increased with duration of use (P for trend = .05). The estimate was highest for women who used oral contraceptives during the cycle in which they became pregnant (relative risk = 4.0; 95% CI=1.6-10), but there was no consistent pattern according to the time interval since last use. Separate analyses of choriocarcinoma and persistent mole yielded similar results, i.e., the relative risk estimates for oral contraceptive use were 2.2 (95% CI=0.8-6.4) and 1.8 (95% CI=1.0-3.0), respectively. Control for the number of sexual partners, which was independently associated with risk (P for trend = .05), did not materially change the results.

CONCLUSIONS

This study, the largest to date, indicates that long duration of oral contraceptive use before conception increases the risk of gestational trophoblastic tumors. These findings may provide clues to the pathogenesis of this rare disease. Changes in use of oral contraceptives are not warranted, however, because the incidence attributable to oral contraceptive use is very low.

Obesity and hypertension among college-educated black women in the United States

It is established that obesity is an important risk factor for hypertension, but there is little information on this relationship among highly educated black women. We assessed the relationship of body mass index (weight (kg)/height2 (m)) to prevalent hypertension among US black women who had completed college, and among less educated women as well. The data were collected in 1995 in the Black Women's Health Study: 64530 African-American women aged 21 to 69 years enrolled by completing mailed health questionnaires; 44% of the participants had completed college. We compared the 9394 participants who reported a diagnosis of hypertension treated with a diuretic or antihypertensive drug (cases) with 9259 participants of similar ages who did not have hypertension (controls). Multivariate odds ratios were estimated by logistic regression. The odds ratio for treated hypertension increased with increasing body mass index at every educational level. Among college-educated women, the odds ratio for hypertension was 2.7 for overweight women (index 27.3-32.3) and 4.9 for severely overweight women (index > or =32.3), relative to women with a body mass index <22.8. The prevalences of obesity and hypertension were high among the college-educated women, although not as high as among women with fewer years of education. About a quarter of the difference in the prevalence of hypertension across educational levels was explained by the difference in the proportions who were overweight or severely overweight. These results document a high prevalence of obesity and hypertension, and a strong association of obesity with hypertension, among highly educated US black women.

Refresher training and continuing education for para-medical ophthalmic assistants

This paper describes a refresher training and continuing education programme in clinical and community ophthalmology for para-medical ophthalmic assistants (PMOAs) conducted by the Lions Aravind Institute of Community Ophthalmology. The course participants included 60 PMOAs working either in district hospitals, primary health centres or mobile units from the districts in Maharashtra. Each training programme was spread over 43 hours in 4 days and included lectures, practical demonstrations, and hands-on training in the outpatient, inpatient, and operation theatre of the training institution. Participants were given exposure to outreach activities in an eye camp and a satellite eye centre resembling a district hospital. The PMOAs found the training to be useful and it was seen that areas like patient counselling, instrument and equipment maintenance, and assistance in the operation theatre for newer surgical procedures which were lacking in the basic training were fulfilled in this training programme. Regional Institutes of Ophthalmology, upgraded medical colleges, and other eye-care institutions which have facilities and manpower could organise similar refresher and continuing education programmes for PMOAs so that they could be utilised more efficiently in the blindness-control activities in the country.

The diagnosis of renal cell cancer in relation to hypertension (United States)

OBJECTIVES

Renal cell cancer has been associated with hypertension or with drugs to treat it in several studies. We assessed whether the association is explained by more frequent detection of early renal cell cancer among persons being treated for hypertension.

METHODS

The data were collected in our Case-Control Surveillance Study, in which patients aged 20 to 69 years were interviewed in hospitals in Baltimore, Boston, New York, and Philadelphia during 1976-1996. We compared 134 incident cases of renal cell cancer who were being treated with drugs for hypertension to 193 untreated cases with respect to the route to diagnosis and the stage.

RESULTS

The relative risk estimate for having been diagnosed incidentally during a routine examination or workup for another condition, relative to having been diagnosed because of symptoms of renal cell cancer, was 1.3 (95 percent confidence interval, 0.7-2.5). The estimate for diagnosis at stage I or II relative to stage III or IV was 1.2 (0.7-2.1).

CONCLUSION

In Case-Control Surveillance Study data, the relative risk estimate for renal cancer among users of various classes of antihypertensive drugs is 1.8 or 1.9. The present results suggest that this association can, at most, be explained only partially by the selective diagnosis of renal cell cancer among persons being treated for hypertension.

Socio-demographic determinants of antenatal care

A large scale community-based study in South Kanara district of Karnataka state, India has revealed that, despite a low infant mortality rate (IMR), there is a clear association between IMR and lack of antenatal care (ANC) as well as IMR and poor quality ANC. We analyse the factors which determine the utilization of ANC and show the association between quality of ANC and maternal literacy, occupation, age and parity. Factors which are also significantly associated are socio-economic status, religion and matriarchal system. Characteristically, those who do not receive any ANC are poor, illiterate, multiparous unskilled mothers over 30 years of age and who live far away from a medical facility. This study conclusively demonstrates that even in regions where IMR is low there is enough scope to reduce it further by concentrating our efforts on the high risk population.

Perinatal mortality in a rural district of south India

Perinatal mortality is one of the most sensitive indices of maternal and child health. The perinatal mortality rate is an indicator of the extent of pregnancy wastage as well as of the quality and quantity of health care available to the mother and the newborn. A community based prospective study carried out on 13,214 births in South Kanara district between Oct. 1991-Sept. 1992 revealed a perinatal mortality rate (PNMR) of 44.65/1000 births. Among the various factors influencing perinatal mortality, breech deliveries and babies of multiple pregnancies had a very high perinatal mortality rate of 180.81/1000 births (adjusted odd's ratio: 4.90) and 128/1000 births (adjusted odd's ratio: 2.64). The previous bad obstetric history of the mother, parity and sex of the newborn were among the other important factors influencing the PNMR.

EARLY CARCINOMA TONGUE - SURGICAL OPTIONS

A retrospective analysis of 127 surgically treated cases of T-1, T-2 carcinoma of oral tongue during the period 1987-1990 was undertaken. 68.5 per cent (87) underwent hemiglossectomy and 31.5 per cent (40) underwent wide excision. There were loco-regional recurrences in 22 per cent (27). In the hemiglossectomy group 9 per cent (8 of 87) had local recurrences compared to 25 per cent (10 of 40) of wide excision group, (P = 0.01). Mean disease free survival was 40 months and 33 months for hemiglossectomy group and wide excision group respectively, (P = 0.006). It is seen that local recurrences are significantly less for the hemiglossectomy group compared to the wide excision group.

Calcium channel blockers and the risk of cancer

CONTEXT

Recent epidemiologic studies have raised the concern that calcium channel blocker use may increase the risk of cancer overall and of several specific cancers.

OBJECTIVE

To assess whether calcium channel blocker use increases the risk of cancer overall and of specific cancers.

DESIGN

Case-control drug surveillance study based on data collected from 1983 to 1996.

SETTING

Hospitals in Baltimore, Md, New York, NY, and Philadelphia, Pa.

PATIENTS

A total of 9513 patients aged 40 to 69 years with incident cancer of various sites and 6492 controls aged 40 to 69 years admitted for nonmalignant conditions.

MAIN OUTCOME MEASURES

Incident cancer overall and 23 specific cancers.

RESULTS

Calcium channel blocker use was unrelated to the risk of cancer overall (relative risk [RR], 1.1; 95% confidence interval [CI], 0.9-1.3). Use was not significantly associated with increased risks of individual cancers, including those previously implicated, except cancer of the kidney (RR, 1.8; 95% CI, 1.1 -2.7). Recent use, use for 5 or more years, and use of individual calcium channel blocker drugs were also not associated with cancer incidence. Use of beta-blockers and angiotensin-converting enzyme inhibitors was generally unrelated to cancer overall or individual cancers, but both were associated with kidney cancer (RR, 1.8; 95% CI, 1.3-2.5; and RR, 1.9; 95% CI, 1.2-3.0, respectively).

CONCLUSIONS

The present study suggests that the use of calcium channel blockers is unrelated to an increase in the overall risk of cancer or of individual cancers, except kidney cancer, which has been associated with hypertension or drugs to treat hypertension in previous studies.