Non-response did not affect prevalence estimates of asthma and respiratory symptoms - results from a postal questionnaire survey of the general population.

BACKGROUND: A high participation rate is warranted in order to ensure validity in surveys of the general population. However, participation rates in such studies have declined during the last decades. OBJECTIVE: To evaluate the reasons for and potential effects of non-response in a large population-based survey about asthma and respiratory symptoms in Northern Sweden. METHODS: Within the Obstructive Lung Disease In Norrbotten (OLIN) studies, a random sample of 12,000 adults aged 20-79 was invited to a postal questionnaire survey about asthma, allergic rhino-conjunctivitis and respiratory symptoms in 2016. Three reminders were sent. A random sample of 500 non-responders was invited to a telephone interview. RESULTS: The participation rate in the initial mailing was 41.4%, and 9.2%, 5.0%, and 2.6% in the subsequent three reminders and totally 58.3% (n = 6854) responded. Of 500 non-responders selected for telephone interviews, 320 were possible to reach and 272 participated. Male sex, younger age, and current smoking were associated with both late and non-response. The prevalence of asthma and most respiratory symptoms did not differ significantly between responders and non-responders while allergic rhino-conjunctivitis and smoking was more common among non-responders. Reminders increased the participation rate but did not alter risk ratios for smoking and occupational exposures. Reasons for non-response were mainly lack of time and having forgotten to answer. CONCLUSIONS: With a response rate of 58.3%, neither the prevalence estimates of asthma, respiratory symptoms nor the associations to risk factors were affected by non-response, while allergic rhino-conjunctivitis and smoking was underestimated in this Swedish population.

High incidence and persistence of airborne allergen sensitization up to age 19 years.

BACKGROUND: Longitudinal population-based studies about the natural history of allergic sensitization are rare. The aim was to study incidence and persistence of airborne allergen sensitization up to young adulthood and risk factors for early and late onset of sensitization. METHODS: All children aged 7-8 years in two municipalities in Northern Sweden were invited to a parental questionnaire and skin prick tests (SPTs) to ten airborne allergens, and 2148 (88%) participated. The protocol was repeated at age 11-12 and 19 years, and 1516 participated in all three examinations. RESULTS: Prevalence of any positive SPT increased from 20.6% at age 7-8 years to 30.6% at 11-12 years, and 42.1% at 19 years. Animals were the primary sensitizers at age 7-8 years, 16.3%, followed by pollen, 12.4%. Mite and mold sensitization was low. Mean annual incidence of any positive SPT varied between 2.8 and 3.4/100 per year, decreased by age for animal, and was stable for pollen. Sensitization before age 7-8 years was independently associated with family history of allergy, OR 2.1 (95% CI 1.6-2.8), urban living, OR 1.9 (95% CI 1.2-2.9), and male sex, OR 1.3 (95% CI 1.0-1.7), and negatively associated with birth order, OR 0.8 (95% CI 0.7-1.0), and furry animals at home, OR 0.7 (95% CI 0.7-0.9). Incidence after age 11-12 years was associated only with family history of allergy. Multisensitization at age 19 years was significantly associated with early age at sensitization. Remission of sensitization was uncommon. CONCLUSION: The increasing prevalence of allergic sensitization by age was explained by high incidence and persistence. After age 11-12 years, the factors urban living, number of siblings, and male sex lost their importance.

Effect of adjuvant androgen deprivation on thyroid function tests in prostate cancer patients.

Androgen deprivation (AD) used in the treatment of prostate cancer is known to alter concentrations of sex hormones and their binding globulins. Less is known as to its effect on thyroid hormones. In this prospective study the effects of AD on thyroid function were clarified. Levels of serum thyroid stimulating hormone (TSH), free thyroxine (FT4) and thyroid binding globulin concentrations were measured in prostate cancer patients treated with either radical radiotherapy and androgen deprivation for 12 months (AD) or radical radiotherapy alone (RT). Measurements were made at baseline, and at 3, 6 and 12 months. At baseline and at 3 months the results of thyroid function tests did not differ significantly between groups. A significant decline in serum testosterone in the AD group was accompanied by a significant decline in FT4 at 6 and 12 months, while no significant changes in thyroid function were observed in the RT group. The decline in FT4 among AD patients did not evoke a normal TSH response. Prolonged use of AD hampers the interpretation of thyroid test results. This finding has substantial implications for the follow-up of patients in hormonally treated prostate cancer.

Androgen deprivation and cognition in prostate cancer.

Androgen deprivation (AD) is commonly used in neoadjuvant and adjuvant setting with prostate cancer (PC) radiotherapy. This prospective study assessed whether cognitive functioning is impaired during 12 months of AD therapy. Longitudinal testing of 25 patients treated with AD and curative radiotherapy was undertaken at baseline, and at 6 and 12 months. CogniSpeed software was used for measuring attentional performances. Other cognitive performances were evaluated using verbal, visuomotor and memory tests. The Beck depression inventory was employed to evaluate depressive mood and EORTC QLQ-C30 for quality of life (QoL). During longitudinal testing of the AD group, no impairment in cognitive performances was found. Instead, improvement was observed in object recall (immediate, P=0.035; delayed, P<0.001), and in semantic memory (P=0.037). In QoL, impairment in physical function was observed. Androgen deprivation of 12 months appears to be associated with preserved cognitive functioning, although physical impairment occurs. These results have implications for counseling and psychosocial support of patients in the context of treatment options in PC.

DNA cytometry in diagnostic cytology of the prostate gland.

BACKGROUND: Differential analysis and cytological grouping of fine needle aspiration biopsy (FNAB) samples of the prostate are important in practice. We used image analytical DNA cytometry to achieve this and also studied the best method of interpretation of the histograms. MATERIALS AND METHODS: Sixty-two FNAB samples of the prostate were stained with Feulgen stain and nuclear DNA histograms were produced by image cytometry. The most atypical cell groups were selected for measurements. Also, free epithelial cells between cell groups were studied. The cells presented in the histograms were grouped according to the nuclear DNA content and by application of different gates of observation for diploid status. RESULTS: Several DNA histogram features (histogram classification categories, benign and malignant histogram patterns, presence of >5c-7c cells) showed significant relationships to differential diagnosis. Highly aneuploid (>5c-7c) cells had the potential for distinguishing a progressive-type of prostate cancer. CONCLUSION: The fraction of tetraploid and aneuploid histograms increased from atypical but benign to definitely malignant samples. DNA histograms have potential in the differential diagnosis and evaluation of the progressive character of prostate cancer.

Air quality and ocular discomfort aboard commercial aircraft.

BACKGROUND: Aircraft cabin air quality has been a subject of recent public health interest. Aircraft environments are designed according to standards to ensure the comfort and well-being of the occupants. The upper and lower limits of humidity set by ASHRAE standards are based on the maintenance of acceptable thermal conditions established solely on comfort considerations, including thermal sensation, skin wetness, skin dryness, dry eyes and ocular discomfort. The purpose of this study is to investigate the influence of air (carbon dioxide level, relative humidity, and temperature) aboard commercial aircraft on ocular discomfort and dry eye of aircraft personnel and passengers. METHODS: Measurements of indoor air quality were performed in 15 different aircraft at different times and altitudes. Forty-two measurements of carbon dioxide, temperature, and humidity were performed with portable air samplers every 5 minutes. Passenger loads did not exceed 137 passengers. RESULTS: Thermal comfort rarely met ASHRAE standards. Low humidity levels and high carbon dioxide levels were found on the Airbus 320. The DC-9 had the highest humidity level and the Boeing-767 had the lowest carbon dioxide level. CONCLUSIONS: Air quality was poorest on the Airbus 320 aircraft. This poor level of air quality may cause intolerance to contact lenses, dry eyes, and may be a health hazard to both passengers and crew members. Improved ventilation and aircraft cabin micro-environments need to be made for the health and comfort of the occupants.

Indoor-air quality and ocular discomfort.

BACKGROUND: Almost 25 million workers in 1.2 million commercial buildings in the United States have symptoms of sick building syndrome (SBS). It is a source of ocular discomfort and may exacerbate the successful wear of contact lenses. This study examines the relationship between SBS and oculovisual discomfort. METHODS: Measurements of carbon dioxide, formaldehyde, temperature, and humidity were performed in 12 public office buildings that contained a total of 877 occupants. A questionnaire survey of the occupants was also performed. RESULTS: Thirty-five percent of the occupants of the buildings were dissatisfied with the indoor-air quality. Twenty-nine percent of the office building occupants reported ocular discomfort. CONCLUSION: There was a significant correlation between eye irritation, throat irritation, and symptoms of blurred near vision. Ocular discomfort could be an indicator of poor indoor-air quality and a sick building syndrome.

Validity of ambulatory 24-h oesophageal pH measurement in the diagnosis of reflux disease.

The validity of 24-h oesophageal pH recording was studied in 100 consecutive patients who had gastro-oesophageal reflux (GER) symptoms and had indications for a 24-h pH recording. The aim was to explore the relationship of patient symptoms, endoscopic findings and histopathological analysis of oesophageal mucosa with the findings in pH recording. Among these patients with typical GER symptoms, the multiplicity of symptoms or their nature did not differentiate them, but in all groups abnormal amounts of reflux were present, as compared with usual reference pH recording values. Yet, among these symptomatic patients, the macroscopic severity of oesophagitis and histologically defined oesophagitis were related to increased abnormality of 24-h pH recording. The results suggest that 24-h pH recording of the oesophagus gives a good indication of the severity of gastro-oesophageal reflux disease and, as such, superior to patient symptoms.

New X-linked syndrome with severe mental retardation, severely impaired vision, severe hearing defect, epileptic seizures, spasticity, restricted joint mobility, and early death.

A family with an X-linked mental retardation syndrome involving seven children in two generations is reported. The syndrome includes microcephaly, severe mental retardation, optic atrophy with severely impaired vision or blindness, a severe hearing defect, spasticity, epileptic seizures, restricted movement of the large joints, and death in infancy or early childhood. We conclude that this is a distinct, previously unrecognized X-linked mental retardation syndrome.

Ocular hypersensitivity to thimerosal in rabbits.

Rabbits were immunized to thimerosal conjugates and challenged with specific antigen-sensitized contact lenses. The symptoms of acute ocular hypersensitivity observed included corneal edema, corneal infiltration and erosion, infiltration of the anterior chamber, iritis, conjunctival edema and hyperemia, and a significant increase in mucous production. Occasional evidence of corneal neovascularization and giant conjunctival papillae were seen. All these parameters were assessed on a five-point scale (0 to +4) and tabulated as an ocular index. The index of ocular hypersensitivity correlated with the titers of the serum antibodies to thimerosal. The major class of serum antibodies consisted of immunoglobulin (Ig) G, with IgA compromising approximately 5% of serum antibodies. During the ocular challenge, the total and IgG tear antibody titers increased as a result of increased vascular permeability. The tear IgA titers increased to a lesser extent than IgG. The influx of serum proteins directly into the tear film was confirmed by a protein-dye tracer technique. Histologic analysis showed that the ocular inflammatory response was accompanied by both polymorphonuclear and mononuclear cell infiltrates into the cornea and conjunctiva. In conclusion, thimerosal-immunized rabbits show an exquisite sensitivity to the minute quantities of thimerosal conjugates adsorbed to contact lenses. Both serum and tear antibodies correlate with the severity of the ocular inflammatory response. This model would appear to simulate an antibody-mediated immune complex or Arthus type of ocular hypersensitivity commonly seen to foreign antigens including preservatives.

Adsorption and removal of protein bound to hydrogel contact lenses.

Tear film proteins are known to adsorb to new hydrogel contact lenses. Using a radioiodine tracing technique, proteins were shown to adsorb to contact lens surfaces. The quantity of protein adsorbed to the contact lenses within 2 to 4 h was 1 to 3 micrograms/lens. The degree of protein adsorption varied from lens-to-lens depending in part on the water content of the lens. High water content ionic lenses bound the most protein, whereas lower water content and nonionic lenses bound less protein. Enzyme cleaning of the protein-coated contact lenses removed about 75% of the adsorbed protein. When the enzyme-cleaned lenses were reincubated with protein, similar quantities were quickly readsorbed within a similar period of time. The rate of readsorption appeared to vary with the type of enzyme used to clean the lenses. Hydrogel lenses adsorb protein from the tear film rapidly and irreversibly. Cleaning the lenses has only a partial and temporary effect on the bound protein. The lens-bound proteins could become partly denatured during their binding to the lenses. These observations suggest a possible role for such proteins in ocular sensitivity to contact lenses.

Thimerosal: an ophthalmic preservative which acts as a hapten to elicit specific antibodies and cell mediated immunity.

A rabbit model for the study of hypersensitivity to thimerosal was established in order to develop better techniques for screening patient sera and tears for specific antibodies to lens care re-agents. Thimerosal (sodium ethylmercury thiosalicylatelate) was successfully coupled to several protein carriers using a water soluble carbodiimide which linked the carboxyl group of thimerosal to free amino groups of the carrier proteins. Thimerosal was also shown to spontaneously react with proteins as detected by the irreversible binding of mercury to the protein carrier. Immunization of rabbits with the chemically coupled thimerosal resulted in the production of antibodies which specifically reacted with thimerosal. The rabbits also manifested delayed and immediate forms of hypersensitivity to the thimerosal conjugates. The ELISA assay for specific serum antibodies was found to be a sensitive, reliable and specific screening tool However, there was no immunological cross reactivity between the chemically coupled thimerosal and the spontaneously coupled thimerosal. Therefore, the epitopes produced by these two reaction mechanisms were probably immunochemically different even though both contained detectable thimerosal derived mercury.

Pinealoma.

A patient was admitted to the Emergency Department of the Montreal General Hospital and referred to the Ophthalmology Clinic. He reported disorientation, dizziness, frontal headaches, and near vision problems. He had reduced near vision, binocular vision anomalies, Collier's sign, and abnormal pupil sizes, shapes, and responses. A diagnosis of pinealoma with a poor prognosis due to metastases was made.

Monocular photophobia.

Uniocular eye closure in bright daylight has been considered as evidence of a binocular vision anomaly. Two groups of patients with various binocular vision anomalies were studied and compared. The control group did not manifest uniocular or binocular photophobia while the experimental group admitted frequent eye closure. The variables studied included anisometropia, refractive error, suppression, amblyopia, heterophoria and strabismus. No relations were observed between academic achievement and anomalies of binocular vision utilizing three analytical methods. Monocular photophobia was not associated with anomalous binocular vision.

The effects of PUVA on the eye.

Psoriasis is a common skin disease which may be treated with 8-methoxy psoralen and long-wave ultraviolet light (PUVA). Eye protection is provided during and after treatment to prevent the development of photokeratitis and cataracts. Fifteen patients, treated with medication and ultraviolet A (UVA) had an initial complete eye examination and a repeat examination after each treatment. No patients developed cataracts but almost one-half of the patients had a mild form of photokeratoconjunctivitis. The ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye syndrome.

Blood cadmium and plasma zinc measurements in acute myocardial infarction.

Blood cadmium and plasma zinc were measured in a series of 47 patients admitted for myocardial infarction (MI) and in 37 control subjects divided into 3 groups. Certainly increased blood cadmium values, for the MI patients, were found in 33%. The mean blood cadmium value of the MI series was significantly (P less than 0.001), but not invariably, higher against the control subjects. The difference between the zinc values of the series was studied in 35 MI patients with raised serum enzyme activity. In MI patients, the mean plasma zinc content was significantly (0.001 less than P less than 0.01) lower than in healthy controls. Of the enzymes, the highest positive correlation was found between the ratio of blood cadmium to plasma zinc and the GOT activity. Of the ratio, the MI patients had values in excess of the controls range in 43%, and values within the limits of the healthy controls in 40%. Therefore, the rise in the ratio is of limited value for the diagnosis of myocardial infarction in an individual patient.

How environment affects visual development: a selected review.

This selected review covers 60 papers on animal and human studies in which the development of vision, particularly the neural pathways, has been investigated in terms of environmental stimuli or their absence. Most of these studies are summarized in a single table. Emphasis is given to the early treatment of vision deficits.

Medicare in Quebec.

A provincial health insurance system was introduced through Canada more than five years ago. The program and fee schedules for optometric and some ophthalmologic services are presented. Statistics are provided by the government concerning the utilization of optometric and some medical eye services according to the distribution of age and sex in the Quebec population. Relative costs of these services as well as the incomes of health care professionals are compared. It is hoped that this information will aid in the planning and development of the U.S. Medicare program.