Occurrence of COVID-19 and serum per- and polyfluoroalkyl substances: A case-control study among workers with a wide range of exposures

Per- and polyfluoroalkyl substances (PFAS) are a broad class of synthetic chemicals; some are present in most humans in developed countries. Some studies suggest that certain PFAS may have immunotoxic effects in humans, which could put individuals with high levels of exposure at increased risk for infectious diseases such as COVID-19. We conducted a case-control study to examine the association between COVID-19 diagnosis and PFAS serum concentrations among employees and retirees from two 3 M facilities, one of which historically generated perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and perfluorohexane sulfonic acid (PFHxS). Participants completed enrollment and follow-up study visits in the Spring of 2021. Participants were categorized as cases if they reported a COVID-19 diagnosis or became sick with at least one symptom of COVID-19 when someone else in their household was diagnosed, otherwise they were categorized as a control. COVID-19 diagnosis was modeled in relation to concentration of serum PFAS measured at enrollment after adjusting for covariates. The analytic sample comprised 573 individuals, 111 cases (19.4%) and 462 controls (80.6%). In adjusted models, the odds ratio of COVID-19 was 0.94 per interquartile range (14.3 ng/mL) increase in PFOS (95% confidence interval 0.85, 1.04). Results for PFOA, PFHxS, and perfluorononanoic acid (PFNA) were similar. Other PFAS present at lower concentrations were examined as categorical variables (above the limit of quantification [LOQ], yes vs. no [referent category]), and also showed no positive associations. In our study, which used individual-level data and included people with high occupational exposure, the serum concentrations of all PFAS examined were not associated with an increased odds ratio for COVID-19. At this point, the epidemiologic data supporting no association of COVID-19 occurrence with PFAS exposure are stronger than those suggesting a positive association.

An investigation of 3M Cordova, IL production worker's per- and polyfluoroalkyl substances biomonitoring results and mortality experience

Per- and polyfluoroalkyl substances (PFAS) are a wide-ranging group of chemicals that have been used in a variety of polymer and surfactant applications. While 3M Cordova, Illinois was not one of 3M's primary manufacturing facilities for the legacy long-chain PFAS (PFOS, PFOA, PFHxS), it has been a major manufacturing site for short-chain PFAS (compounds that are or may degrade to PFBS or PFBA). The purpose of this research focused on: 1) an analysis of biomonitoring data of employees and retirees, and 2) an analysis of the cohort mortality of workers from 1970 to 2018. Employees had higher PFBS and PFBA serum concentrations than the retirees, while retirees had higher concentrations for PFOS, PFOA, and PFHxS. Compared to the 2017-2018 NHANES data, employees' PFOS and PFHxS concentrations in 2022 were two-fold higher, with PFOA levels comparable. These NHANES data did not include serum PFBS or PFBA. Cross-sectional trends of PFOS and PFOA levels from 1997 to 2022 showed PFOS declined from 151 ng/mL to 10.4 ng/mL. Similarly, PFOA decreased from 100 ng/mL to 1.5 ng/mL. A longitudinal analysis of 48 participants with measurements in both 2006 and 2022 showed concentrations decreased by 74% for PFOS and 90% for PFOA. In the mortality study, 1707 employees who worked 1 day or longer were followed for an average of 25.6 years and had 143 (8%) deaths. There were no significantly elevated risks for any specific cause of death, regardless of latency period (0 or 15 years). While no specific PFAS exposures were examined, worker mortality experience (1970-2018) was analyzed by major departments representing primary work areas. Employees and retirees at the Cordova facility continue to have elevated PFOS and PFHxS serum concentrations compared to the general population, however, their legacy PFAS concentrations have declined over time, consistent with the estimated serum elimination half-lives of these PFAS in humans assuming nominal ambient exposures. For PFBS and PFBA, the results indicated no long-term accumulation in the blood likely due to their short serum elimination half-lives. After nearly 50 years of follow-up, this Cordova workforce showed no increased risk of mortality from cancer or any other specific cause of death.

Antibody response to COVID-19 vaccines among workers with a wide range of exposure to per- and polyfluoroalkyl substances

Per- and polyfluoroalkyl substances (PFAS) are a broad class of synthetic chemicals; some are present in most humans in developed countries. Several studies have shown associations between certain PFAS, such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), and reduced antibody concentration after vaccination against diseases such as Tetanus. Recent studies have reported associations between COVID-19 occurrence and exposure to certain types of PFAS. However, studies of antibody concentration after COVID-19 vaccination in relation to PFAS serum concentrations have not been reported. We examined COVID-19 antibody responses to vaccines and PFAS serum concentrations among employees and retirees from two 3M facilities, one of which historically manufactured PFOS, PFOA, and perfluorohexane sulfonic acid (PFHxS). Participants completed enrollment and follow-up study visits in the Spring of 2021, when vaccines were widely available. In total 415 participants with 757 observations were included in repeated measures analyses. Log-transformed concentrations of anti-spike IgG and neutralizing antibodies were modeled in relation to concentration of PFAS at enrollment after adjusting for antigenic stimulus group (9 groups determined by COVID-19 history and number and type of vaccination) and other variables. The fully adjusted IgG concentration was 3.45 percent lower (95% CI -7.03, 0.26) per 14.5 ng/mL (interquartile range) increase in PFOS; results for neutralizing antibody and PFOS were similar. For PFOA, PFHxS, and perfluorononanoic acid (PFNA), the results were comparable to those for PFOS, though of smaller magnitude. In our study data, the fully adjusted coefficients relating concentration of vaccine-induced antibodies to COVID-19 and interquartile range difference in serum concentration of PFOS, PFOA, PFHxS, and PFNA were inverse but small with confidence intervals that included zero. Our analysis showed that the coefficient for the four PFAS examined in detail was considerably affected by adjustment for antigenic stimulus group.

A Pathology Review of the Lower Gastrointestinal Tract in Relation to Ulcerative Colitis in Rats and Cynomolgus Macaques Treated With Ammonium Perfluorooctanoate

Among many short-term, subchronic, and chronic toxicology studies with ammonium perfluorooctanoate (PFOA), the gastrointestinal tract has not been identified as a target organ for PFOA-related toxicity in laboratory animals where the corresponding serum PFOA concentrations typically approach several orders of magnitude higher than the general human population. These lack of gastrointestinal tract-related findings were in direct contrast to an epidemiological observation where a positive trend was observed for ulcerative colitis, an idiopathic chronic inflammatory condition of the gut, in a Mid-Ohio River community whose drinking water contained higher levels of PFOA. This study was conducted to perform a histological reevaluation of large intestine sections in laboratory animals from 2 long-term toxicological studies: one was with Sprague Dawley rats that received ammonium PFOA in their diet for 2 years and the other one was with cynomolgus macaques that received daily capsules of ammonium PFOA for 6 months. In both studies, there was a lack of histological evidence of treatment-related inflammatory lesions that was suggestive of the occurrence of ulcerative colitis in these laboratory animals even under the most rigorous treatment schedules. These findings do not offer support for the biological plausibility of the epidemiological associations reported.

Occupational injury risk by sex in a manufacturing cohort

OBJECTIVES

This study expands previous research comparing injury risk for women and men in a cohort of 24,000 US aluminium manufacturing workers in 15 facilities from 2001 to 2010.

METHODS

We compared injury rates (all injury, first aid, medical treatment, restricted work and lost work time) by sex and by job and sex. Using a mixed effect modelling approach, we calculated ORs and 95% CIs adjusting for age, job tenure, ethnicity and year as fixed effects and person, job and plant as random effects. Additionally, we modelled the data stratified by plant type to examine potential differences in injury risk between smelter (generally recognised as more hazardous) and fabrication production environments.

RESULTS

Risk of injury was higher for women in four out of the five injury outcomes: all injuries combined (OR: 1.58, CI 1.48 to 1.67), injuries requiring first aid (OR: 1.61, CI 1.54 to 1.70), injuries requiring medical treatment (OR: 1.18, CI 1.03 to 1.36) and injuries requiring restricted work (OR: 1.65, CI 1.46 to 1.87). No difference in the risk of lost time injury by sex was found in this cohort. Analyses stratified by plant type showed similarly elevated injury risk for women, although the risk estimates were higher in smelters than fabrication plants.

CONCLUSIONS

To our knowledge, this is the largest single-firm study examining injury risk by sex with sufficient data to appropriately adjust for job. We show a consistently higher injury risk for women compared with men in the smelting and fabrication environments.

Effect of systematic ergonomic hazard identification and control implementation on musculoskeletal disorder and injury risk

OBJECTIVES

This study aimed to examine the effect of an ergonomic hazard control (HC) initiative, undertaken as part of a company ergonomics standard, on worker injury risk.

METHODS

Using the company's ergonomic hazards database to identify jobs with and without ergonomic HC implementation and linking to individual job and injury histories, injury risk among person-jobs with HC implementation (the HC group) was compared to those without HC (NoHC group) using random coefficient models. Further analysis of the HC group was conducted to determine the effect of additional ergonomic hazards controlled on injury risk.

RESULTS

Among 123 jobs at 17 plant locations, 347 ergonomic hazards were quantitatively identified during the study period. HC were implemented for 204 quantified ergonomic hazards in 84 jobs, impacting 10 385 persons (12 967 person-jobs). No HC were implemented for quantified ergonomic hazards in the remaining 39 jobs affecting 4155 persons (5046 person-jobs). Adjusting for age, sex, plant origin, and year to control for any temporal trend in injury risk, the relative risk (RR) for musculoskeletal disorder (MSD) was 0.85 and the RR for any injury or MSD was 0.92 in the HC compared to NoHC group. Among the HC group, each ergonomic hazard controlled was associated with risk reduction for MSD and acute injury outcomes (RR 0.93).

CONCLUSION

Systematic ergonomic HC through participatory ergonomics, as part of a mandatory company ergonomics standard, is associated with MSD and injury risk reduction among workers in jobs with HC implemented.

An evaluation of surgical outcome of bilateral cleft lip surgery using a modified Millard's (Fork Flap) technique

BACKGROUND

The central third of the face is distorted by the bilateral cleft of the lip and palate and restoring the normal facial form is one of the primary goals for the reconstructive surgeons. The history of bilateral cleft lip repair has evolved from discarding the premaxilla and prolabium and approximating the lateral lip elements to a definitive lip and primary cleft nasal repair utilising the underlying musculature. The aim of this study was to review surgical outcome of bilateral cleft lip surgery (BCLS) done at the Lagos University Teaching Hospital.

MATERIALS AND METHODS

A review of all cases of BCLS done between January 2007 and December 2012 at the Lagos University Teaching Hospital was done. Data analysis included age and sex of patients, type of cleft deformity and type of surgery (primary or secondary) and whether the cleft deformity was syndromic and non-syndromic. Techniques of repair, surgical outcome and complications were also recorded.

RESULTS

A total of 39 cases of BCLS involving 21 males and 18 females were done during the period. This constituted 10% (39/390) of all cases of cleft surgery done during the period. There were 5 syndromic and 34 non-syndromic cases. Age of patients at time of surgery ranged between 3 months and 32 years. There were 24 bilateral cleft lip and palate deformities and 15 bilateral cleft lip deformities. Thirty-one of the cases were primary surgery, while 8 were secondary (revision) surgery. The most common surgical technique employed was modified Fork flap (Millard) technique, which was employed in 37 (95%) cases.

CONCLUSION

Bilateral cleft lip deformity is a common cleft deformity seen in clinical practice, surgical repair of which can be a challenge to an experienced surgeon. A modified Fork flap technique for repair of bilateral cleft lip is a reliable and versatile technique associated with excellent surgical outcome.

Pattern of presentation and management of lip injuries in a Nigerian hospital

AIM

Human lip injuries, although uncommon, present major challenges in terms of reconstructive options and the outcome of surgical management. The reconstructive techniques are usually varied but the ultimate objectives of treatment are to achieve healing, function, and aesthetics. The aim of this study was to report the etiology, pattern of presentation, and surgical management of lip injuries in Lagos University Teaching Hospital (LUTH).

MATERIALS AND METHODS

A prospective study of consecutive cases of lip injury was conducted at the Oral and Maxillofacial Surgery Clinic of the Lagos University Teaching Hospital. Data collected included age and sex of patients, etiology, pattern of presentation, and surgical techniques of repair.

RESULTS

A total of 13 patients with lip injury to the lip were included in the study (M = 6, F = 7). Human bite (11 cases) was the most common cause of injury followed by electric burns (2 cases). The most (81.8%) frequently affected site was the lower lip. Most patients presented within 72 hours after injury with infected wound. Treatment offered included thorough debridement and primary repair using various surgical techniques. A one-stage surgical technique was employed in all cases. Healing was uneventful in all cases and satisfactory.

CONCLUSION

Most of the lip injuries in the present study were due to human bites with almost equal sex distribution. Lower lip was most commonly affected. All cases were successfully treated by debridement, broad spectrum antibiotic coverage, and one-stage surgical repair with a favorable outcome.

Further validation that claims data are a useful tool for epidemiologic research on hypertension

BACKGROUND

The practice of using medical service claims in epidemiologic research on hypertension is becoming increasingly common, and several published studies have attempted to validate the diagnostic data contained therein. However, very few of those studies have had the benefit of using actual measured blood pressure as the gold standard. The goal of this study is to assess the validity of claims data in identifying hypertension cases and thereby clarify the benefits and limitations of using those data in studies of chronic disease etiology.

METHODS

Disease status was assigned to 19,150 employees at a U.S. manufacturing company where regular physical examinations are performed. We compared the presence of hypertension in the occupational medical charts against diagnoses obtained from administrative claims data.

RESULTS

After adjusting for potential confounders, those with measured blood pressure indicating stage 1 hypertension were 3.69 times more likely to have a claim than normotensives (95% CI: 3.12, 4.38) and those indicating stage 2 hypertension were 7.70 times more likely to have a claim than normotensives (95% CI: 6.36, 9.35). Comparing measured blood pressure values identified in the medical charts to the algorithms for diagnosis of hypertension from the claims data yielded sensitivity values of 43-61% and specificity values of 86-94%.

CONCLUSIONS

The medical service claims data were found to be highly specific, while sensitivity values varied by claims algorithm suggesting the possibility of under-ascertainment. Our analysis further demonstrates that such under-ascertainment is strongly skewed toward those cases that would be considered clinically borderline or mild.

Reasons and pattern of tooth extraction among patients presenting at a Nigerian semi-rural specialist hospital

BACKGROUND

Oral health is greatly influenced by health teeth.

OBJECTIVE

The study is to determine the reasons and pattern of tooth extraction in patients seeking care at the oral surgery/Dental clinic in Rasheed Shekoni Specialist Hospital, Dutse, Jigawa between January 2010 and December 2011.

METHODS

A retrospective review of records of dental extraction patients. Patients' records were analyzed for demographics, reason(s) for tooth extraction and tooth/teeth extracted.

RESULTS

During the 2 years study period, 349 patients (M:F = 1.3:1) aged 2-65 years (mean = 29.7 years +/- 11.5 SD) had extraction of 377 teeth. Dental caries and its sequelae (91.2%) was the most frequent reason for tooth extraction across all age groups, followed distantly by periodontal disease (3.2%) and recurrent pericoronitis (3.0%). The highest proportion of extraction occurred between age 21 to 30 years of age. Mandibular first molars were the most commonly extracted tooth due to dental caries, followed by maxillary first and mandibular second molars. Mandibular molars were by far the more frequently extracted than maxillary molars.

CONCLUSION

Dental caries and its sequelae was the main reason for removal of teeth in this section of Nigerian population. Therefore, there is urgent need to focus on the prevention and treatment of dental caries and its sequelae in order to maintain functional and healthy teeth throughout life.

Pattern of periodontal treatments performed at the periodontology clinic of the Lagos University Teaching Hospital: 22 months review

BACKGROUND

A critical evaluation of the pattern of periodontal procedures performed is important in providing useful data to the administrator for proper planning and budgeting for dental health service.

OBJECTIVE

To assess the pattern of periodontal treatments performed over a given period of time at the Periodontology clinic of the Lagos University Teaching Hospital, Lagos, Nigeria.

METHODS

This was a twenty two months retrospective study of all periodontal procedures performed on patients seen at the periodontology clinic of the Lagos University Teaching Hospital between January 2006 and October 2007. The periodontology treatment record was used to retrieve information which included the patient's age, gender, diagnosis and periodontal procedures given. The procedures were further categorized into surgical and nonsurgical groups. The information obtained was then analyzed using Epi Info 2007 statistical software.

RESULTS

A total of 1,938 patients were seen during this period. Females were 1009 (52.1%) and males were 929 (47.9%). (F/M, 1.1:1). A total of 2,110 periodontal treatments were performed. Majority of the patients received non-surgical periodontal therapy which constituted the bulk (96.3%) of the therapies. Scaling and polishing was the most frequently performed non-surgical procedure accounting for 1261 (62.1%) with slightly more males receiving the treatment. Of the surgical treatment modalities, operculectomy accounted for 65.4% and was carried out on more females than males. Regenerative procedures were the least performed surgical treatments.

CONCLUSION

This study highlighted that non-surgical periodontal therapy, particularly scaling and polishing was the most frequently utilized periodontal procedure. Operculectomy was the predominant surgical procedure performed. The low percentage of regenerative surgical procedures was however below the desired expectation.

Mid-facial fractures: a 5-year retrospective review in a Nigerian teaching hospital

OBJECTIVE

The aim of this study is to establish the pattern and actiology of mid-facial fractures, of patients seen and treated at the Lagos University Teaching Hospital, Lagos, Nigeria over a 5-year period.

MATERIALS AND METHODS

All cases of midfacial fractures diagnosed and treated at the Department of Oral and Maxillofacial Surgery, Lagos University Teaching Hospital (LUTH), Lagos between January 2004 and December 2008 were reviewed. Data collected from case records of patients included age, sex, aetiology of fracture, anatomic site of fracture, associated maxillofacial fracture, types of treatment and postoperative complications.

RESULTS

The leading cause of mid-facial fractures was road traffic crashes (RTC) which occurred in 93% of highest incidence of mid-facial fractures (36.5%) occurred in the age group of 21-30 years and the lowest in the age group of 60 years and above (2.6%); with male preponderance in nearly all age groups. Female patients were significantly younger than their male counterparts (P=0.000). The most common site of mid-facial bone fractures was the zygomatic complex (n=89, 44.5%), followed by dento-alveolar (n=26, 13%), and Le fort II (n=23, 12%). Conservative management of the fractures was employed in 2.6% (n=4) of the cases while 97.4% (n=152) of the patients required surgical, intervention

CONCLUSIONS

Mid-facial fractures were most common in the 3rd decade of life; with a male-to-female ratio of 3.7: 1. Over 93% of the cases were due to road traffic crashes. Zygomatic complex was the most commonly fractured site. The fact that road traffic crashes still remain the major cause of mid-facial fracture in the studied environment is an indication that the enforcement of legislation to prevent road traffic crashes needs to be re-emphasised.

A survey of facial nerve dissection techniques in benign parotid surgery among maxillofacial and ear, nose, and throat surgeons in Nigeria

OBJECTIVE

The aim of the present study is to identify the facial nerve dissection technique routinely used during parotidectomy for benign parotid tumors by Nigerian Oral and Maxillofacial (OMF) and Ear, Nose, and Throat (ENT) Surgeons.

MATERIALS AND METHODS

A questionnaire-based study was conducted among Oral and Maxillofacial and Ear, Nose, and Throat Surgeons in Nigeria, on their experience with antegrade and retrograde facial nerve dissection techniques in parotid surgery. The respondents were asked to indicate their choice of dissection techniques in revision parotidectomy, limited superficial parotidectomy, and in obese patients with large tumors. They were also asked to indicate if they routinely used perioperative facial nerve monitoring devices in parotid surgery for benign tumors.

RESULT

About half (47.5%) of them routinely used the antegrade technique, while only a few (12.5%) used the retrograde technique. A large number of them (40%), however, used a combination of antegrade and retrograde routinely. Technical ease was the main reason for the choice of technique. The antegrade technique was the technique of choice by most respondents for revision parotidectomy (60%) and limited superficial parotidectomy (62%). However, the retrograde approach was the technique of choice by most of them (47%) in case of parotidectomy in obese patients with large tumors. The routine use of perioperative facial nerve monitoring devices is an uncommon practice among OMF and ENT surgeons in Nigeria.

CONCLUSIONS

The antegrade approach for facial nerve dissection is the most common technique used in parotid surgery by Nigerian OMF and ENT surgeons. Nigerian surgeons need to consider the retrograde approach in selected cases of parotid surgery especially for localized tumors that are amenable to limited superficial parotidectomy. Inclusion of perioperative facial nerve monitoring devices is also advocated.

Recognizing occupational illnesses and injuries

Given the burden of occupational illnesses and injuries in the United States, family physicians should understand the role workplace exposures may play in patients' chief concerns. Incorporating employment screening questions into patients' intake questionnaires is an efficient means of identifying potential occupational causes of symptoms. Recommended questions include what kind of job patients have; whether their symptoms are worse at work; whether they are or have been exposed to dust, fumes, chemicals, radiation, or loud noise; and whether they think their health problems may be related to their work. These questions are especially important when the diagnosis or etiology is in doubt. Depending on patients' responses to the screening questions, a more detailed occupational history may be appropriate. It can be useful to ask about routine tasks performed during a typical work shift, as well as anything out of the ordinary (e.g., a change in routine, an injury or accident). The occupational history should include information about alcohol and tobacco use, second or part-time jobs, military service, hobbies, and home environment. Patients with suspected occupational illnesses or injuries may benefit from referral to an occupational medicine specialist for a more detailed assessment and follow-up.

Prevalence of beryllium sensitization among aluminium smelter workers

BACKGROUND

Beryllium exposure occurs in aluminium smelters from natural contamination of bauxite, the principal source of aluminium.

AIMS

To characterize beryllium exposure in aluminium smelters and determine the prevalence rate of beryllium sensitization (BeS) among aluminium smelter workers.

METHODS

A population of 3185 workers from nine aluminium smelters owned by four different aluminium-producing companies were determined to have significant beryllium exposure. Of these, 1932 workers participated in medical surveillance programmes that included the serum beryllium lymphocyte proliferation test (BeLPT), confirmation of sensitization by at least two abnormal BeLPT test results and further evaluation for chronic beryllium disease in workers with BeS.

RESULTS

Personal beryllium samples obtained from the nine aluminium smelters showed a range of <0.01-13.00 μg/m(3) time-weighted average with an arithmetic mean of 0.25 μg/m(3) and geometric mean of 0.06 μg/m(3). Nine workers were diagnosed with BeS (prevalence rate of 0.47%, 95% confidence interval = 0.21-0.88%).

CONCLUSIONS

BeS can occur in aluminium smelter workers through natural beryllium contamination of the bauxite and further concentration during the refining and smelting processes. Exposure levels to beryllium observed in aluminium smelters are similar to those seen in other industries that utilize beryllium. However, compared with beryllium-exposed workers in other industries, the rate of BeS among aluminium smelter workers appears lower. This lower observed rate may be related to a more soluble form of beryllium found in the aluminium smelting work environment as well as the consistent use of respiratory protection.

Pregnancy epulis associated with life threatening haemorrhage in a Nigerian woman

Pregnancy tumour is a clinical term used to identify a pyogenic granuloma that occurs in pregnant women. Pregnancy tumour is not uncommon, but severe bleeding associated with the lesion necessitating blood transfusion is rare. We report a rare case of mandibular gingival pregnancy tumour with a life-threatening haemorrhage in a 25-year-old Nigerian woman. The patient had lost an estimated 2 litres of blood before presentation. Her packed cell volume was 8% at presentation. The patient was managed by infusion of fluid, transfusion of 4 units of blood and ligation of the facial artery; and excision of the lesion. Following an uneventful healing, she was discharged 10 days later with a PCV of 40.5%. Following subsequent review there was a recurrence 2 months later that regress after 1 month. She was subsequently lost to further follow up.

Overweight and obesity among patients attending a Nigerian oral surgery clinic: implications for oral surgical practice in Nigeria

AIM

To determine the prevalence of overweight and obesity among patients attending oral and maxillofacial outpatient clinic of the Lagos University Teaching Hospital, Nigeria; and discuss the clinical and surgical implications that obesity has on the delivery of oral and maxillofacial surgical and anaesthetic care.

METHODS

Consecutive patients presenting to the oral and maxillofacial surgery outpatient clinic at the Lagos University Teaching Hospital, Nigeria over a 4-month period (May-August 2004) were screened for age, sex, height and weight. All of the patients were treated for dentoalveolar surgical procedures (routine and surgical extractions), incisional and excisional biopsies, and enucleation under local anaesthesia.

RESULTS

The BMIs of the studied patients ranged from 16.7 to 39.8 kg/m(2), with a mean of 24.6 +/- 4.5 kg/m(2). Prevalence of excess weight was 39.1%. Thirty-one (11.4%) patients were obese and 75 (27.7%) patients were overweight. A significant difference was observed in the BMIs of male and female patients (P=0.000). The age groups < 30 years had mean BMIs that were considered normal; whereas other age groups above 30 years had mean BMIs that were considered overweight. Prevalence of obesity increases with increasing age. Obese individuals were seen in all the age groups except those < 20 years.

CONCLUSIONS

The prevalence of excess weight (overweight and obesity) in patients presenting in the studied oral and maxillofacial outpatient setting was 39.1%. Oral and maxillofacial surgeon needs to be aware of obesity-/overweight-related medical and surgical issues and take them into consideration when treating these patients.

Sex differences in injury patterns among workers in heavy manufacturing

The objective of the study was to determine if female workers in a heavy manufacturing environment have a higher risk of injury compared with males when performing the same job and to evaluate sex differences in type or severity of injury. By use of human resources and incident surveillance data for the hourly population at 6 US aluminum smelters, injuries that occurred from January 1, 1996, through December 21, 2005, were analyzed. Multivariate logistic regression, adjusted for job, tenure, and age category, was used to calculate odds ratios and 95% confidence intervals for female versus male injury risk for all injuries, recordable injuries, and lost work time injuries. The analysis was repeated for acute injuries and musculoskeletal disorder-related injuries separately. Female workers in this industry have a greater risk for sustaining all forms of injury after adjustment for age, tenure, and standardized job category (odds ratio = 1.365, 95% confidence interval: 1.290, 1.445). This excess risk for female workers persisted when injuries were dichotomized into acute injuries (odds ratio = 1.2) and musculoskeletal disorder-related injuries (odds ratio = 1.1). This study provides evidence of a sex disparity in occupational injury with female workers at higher risk compared with their male counterparts in a heavy manufacturing environment.

Indications for extraction of permanent teeth in a Nigerian teaching hospital: a 16-year follow-up study

AIM

The aim of the present study was to investigate reasons for permanent tooth extraction at the Lagos University Teaching Hospital, Lagos, and compare this with a study done 16 years previously in the same institution, with a view to evaluating trends in reasons for tooth extractions in the studied environment.

METHODS

A retrospective review of patients who had nonsurgical extraction of their teeth at the Lagos University Teaching Hospital, Nigeria between January and December, 2006 was carried out. The following data were retrieved: Age and sex of patients, reason for the extraction and types of tooth removed. The data obtained was compared with similar study done 16 years previously in the same institution.

RESULTS

Caries and its sequelae and periodontal diseases were the main reasons for tooth extraction in both study periods. Caries and its sequelae as a reason for dental extraction in the second period increased by a factor of 1.2 in comparison with the first period, whereas periodontal disease as a reason extraction in the second period decreased by a factor of 2.7. In addition, orthodontic reasons and tooth impaction as a reason for dental extraction increased by a factor of 4 and 1.3 in the second period respectively. In both study periods, most extractions were carried out in patients within age group 11-40 years (1990, 77%; 2006, 62.3%). Teeth most frequently extracted were posterior teeth (1990, 89.2%; 2006, 89.4%).

CONCLUSIONS

Dental caries and its sequelae, and periodontal disease despite being preventable diseases, still remain the two most common reasons for dental extraction in our environment. Therefore, efforts must be made to improve the dental health awareness and status of Nigerian populace to reduce the morbidity associated with the two preventable causes of tooth loss.

Impairment and disability evaluation: the role of the family physician

Physicians are frequently involved in the assessment of impairment and disability as the treating physician, in consultation, or as an independent medical examiner. The key elements of this assessment include a comprehensive clinical evaluation and appropriate standardized testing to establish the diagnosis, characterize the severity of impairment, and communicate the patient's abilities, restrictions, and need for accommodation. In some cases, a functional capacity evaluation performed by a physical or occupational therapist or a neuropsychological evaluation performed by a neuropsychologist may be required to further clarify the functional capacity of the patient. The results of the impairment evaluation should be communicated in clear, simple terms to nonmedical professionals representing the benefits systems. These individuals make the final determination on the extent of disability and eligibility for benefits and compensation under that particular benefits system.

Indications for extraction of third molars: a review of 1763 cases

OBJECTIVE

Third molars have been described as different from other teeth in the oral cavity. They have the highest rate of developmental abnormalities and, most importantly, are last in the eruption sequence. We investigated reasons for third molar teeth extraction in patients attending the outpatient oral surgery clinic of the Lagos University Teaching Hospital, Nigeria.

MATERIALS AND METHODS

A retrospective review of patients who had third molar extractions between January 2001 and June 2006 was conducted. Data retrieved and analysed were: age and sex of patients, indication for extractions, type of teeth extracted, technique of extractions (surgical and non-surgical) and angulations of impaction in case of impacted lower third molars.

RESULTS

A total of 1763 patients (mean age +/-SD, 33.74+/- 13.3 years; range 15 - 92 years) had their third molars extracted during the period. Majority (58%) of them were females. Surgical extraction was carried out in 506 (28.7%) patients while 1257 (71.3%) patients had non-surgical extractions. Caries and its sequela (63.2%) was the major reason for teeth extraction followed by recurrent pericoronitis (26.3%) and periodontitis (9.2%). Only 11 (0.6%) cases were removed for prophylactic reason. Patients who had their teeth removed for caries were significantly younger than those for periodontitis (P=0.000) but older than those for pericoronitis (P=0.000).

CONCLUSIONS

Caries and periodontal diseases occurring in relatively older age group were the major reasons for non-surgical extraction of third molars while recurrent pericoronitis occurring in relatively younger age was the major reason for surgical extraction of impacted third molars. Prophylactic surgical extraction of third molars is not a common practice in our environment.

Incidence and pattern of presentation of dry socket following non-surgical tooth extraction

OBJECTIVES

To determine the incidence and pattern of presentation of dry socket as a complication of intra-alveolar dental extraction at the Lagos University Teaching Hospital.

METHODS

Patients who were referred for intra-alveolar dental extractions under local anaesthesia at the exodontia clinic of the Department of Oral and Maxillofacial Surgery of the Lagos University Teaching Hospital between July and December 2002 were included in the study. The following data were recorded for each patient: biodata, reason for extraction, number and type of teeth extracted, time taken for the extraction to be done, smoking habit, and use of oral contraceptives. Onset of symptoms and type of teeth involved for those with diagnosis of dry socket were also recorded.

RESULTS

Thirty-one teeth (5.6%) of a total of 554 teeth extracted during the period of the study developed dry socket. The mean age (SD) of the 27 patients who developed dry socket was 32.2 +/- 13.0 years, (m; f ratio of 1: 4.4). Most (44.5%) of the patients who presented with dry socket were in the 3rd decade of life, with more than half (59%) of them presenting on the 3rd day following extraction. Mandibular and maxillary teeth were equally affected. Molars and premolars were exclusively affected. Difficulty of extraction was significantly associated with the development of dry socket (p<.05).

CONCLUSION

The incidence of dry socket in our centre is similar to previous reports. Female patients were significantly affected. Difficulty of extraction was significantly associated with the development of dry socket. Non-dressing treatment provided satisfactory relief of the symptoms and subsequent granulation of the socket.

Incidence of asthma among aluminum workers

Exposures to respiratory irritants encountered in aluminum smelters in Europe, Australia, and New Zealand have been suggested as the cause of "potroom asthma." However, there remains disagreement in North America regarding the existence of this entity. This study was designed to assess whether asthma occurs excessively among potroom workers and if so, delineate dose-response relationships for possible causal risk factors. The asthma incidence ratio between potroom and nonpotroom workers after adjusting for smoking was 1.40. Although bivariate analyses showed a relationship between asthma incidence and exposure to total fluoride, gaseous fluoride, particulate fluoride, sulfur dioxide, and smoking, only the effects of gaseous fluoride (relative risk [RR] = 5.1) and smoking (RR = 7.7) remained significant in a multivariate model. Potroom asthma appears to occur at the studied U.S. aluminum smelters at doses within regulatory guidelines.

Biochemical changes elicited by isosaline leaf and stem-bark extracts of Harungana madagascariensis in the rat

Isosaline leaf and stem-bark extracts of Harungana madagascariensis (L) administered intraperitoneally into healthy albino rats of the Sprague-Dawley strain at a dose of 400 mg/kg body weight resulted in a significant elevation of liver, kidney and serum alanine and aspartate aminotransferase activities. Serum urea, total proteins, total triglyceride, cholesterol, pyruvate and lactate were also significantly elevated in the treated rats. While the stem-bark extract significantly increased the blood glucose level, the leaf extract significantly lowered it. However, both extracts significantly reduced supernatant protein concentrations of the liver and kidney. The significant increase in aminotransferase activities and the concomitant reduction in protein concentrations of the liver and kidney suggests increased catabolism of proteins in these organs, while the catabolites produced are probably channelled to other metabolic pathways resulting in the observed hyperpyruvicaemia, hypertriglyceridaemia and lactic acidaemia in the treated animals. The increased serum cholesterol also suggests a probable degenerative change that these extracts may have on membranes. The results obtained clearly indicate that these extracts alter metabolic activities in both the liver and kidney of treated rats and hence, should be employed in herbal preparations with caution.

Pulmonary impairment and disability

Respiratory disorders, including occupational and environmental lung diseases, are prevalent. Physicians are frequently called upon to determine impairment and aid in the assessment of disability caused by these conditions, either as the treating physician or as an independent medical examiner. In this article we reviewed the role of physicians in determining the presence and severity of pulmonary disorders. A comprehensive clinical assessment and appropriate standardized tests, to objectively characterize the severity of impairment, are the key elements of the evaluation. This assessment may also include the physician's opinion regarding causative factors. Finally, disability determination is made by nonclinicians, through administrative means, based on the degree of impairment and a review of circumstances specific to the individual. Knowledge of these components of disability evaluation will help physicians to better serve their patients and supply appropriate data to the adjudicating system.