Seasonal and meteorological impacts on primary spontaneous pneumothorax

Probability of sporadic lymphangioleiomyomatosis in women presenting with spontaneous pneumothorax

BACKGROUND

Sporadic lymphangioleiomyomatosis (S-LAM) is a rare low-grade neoplasm of young women characterized by multiple pulmonary cysts leading to progressive dyspnea and recurrent spontaneous pneumothorax (SP). The diagnosis of S-LAM may be delayed by several years. To reduce this delay, chest computed tomography (CT) screening has been proposed to uncover cystic lung disease in women presenting with SP. However, the probability to discover S-LAM in this population has not been determined precisely. The aim of this study was to calculate the probability of finding S-LAM in women presenting with (a) SP, and (b) apparent primary SP (PSP) as first manifestation of S-LAM.

METHODS

Calculations were made by applying the Bayes theorem to published epidemiological data on S-LAM, SP and PSP. Each term of the Bayes equation was determined by meta-analysis, and included: (1) the prevalence of S-LAM in the general female population, (2) the incidence rate of SP and PSP in the general female population, and (3) the incidence rate of SP and apparent PSP in women with S-LAM.

RESULTS

The prevalence of S-LAM in the general female population was 3.03 per million (95% confidence interval 2.48, 3.62). The incidence rate of SP in the general female population was 9.54 (8.15, 11.17) per 100,000 person-years (p-y). The incidence rate of SP in women with S-LAM was 0.13 (0.08, 0.20). By combining these data in the Bayes theorem, the probability of finding S-LAM in women presenting with SP was 0.0036 (0.0025, 0.0051). For PSP, the incidence rate in the general female population was 2.70 (1.95, 3.74) per 100,000 p-y. The incidence rate of apparent PSP in women with S-LAM was 0.041 (0.030, 0.055). With the Bayes theorem, the probability of finding S-LAM in women presenting with apparent PSP as first disease manifestation was 0.0030 (0.0020, 0.0046). The number of CT scans to perform in women to find one case of S-LAM was 279 for SP and 331 for PSP.

CONCLUSION

The probability of discovering S-LAM at chest CT in women presenting with apparent PSP as first disease manifestation was low (0.3%). Recommending chest CT screening in this population should be reconsidered.

Influence of meteorological factors on development of spontaneous pneumothorax

This study investigated the correlation between spontaneous pneumothorax (SP) and meteorological factors during different seasons. Patients who visited emergency rooms (ERs) in large cities in Korea and were discharged with SP from 2014 to 2016 were included in this study. Data on temperature, air pressure, and wind speed for each region were collected to obtain each factor's daily maximum, minimum, average, and changes. Days with more than 1 case of SP per million were referred to as pneumothorax days (PD) and those with less than 1 case of SP per million were referred to as non-pneumothorax days (NPD). The environmental factors were assessed on the same day (Day 0), 1 day prior (Day-1), and 2 days prior (Day-2) to PD and NPD per season. A total of 17,846 patients were included in this study. During winter, 4080 patients with SP visited the ERs of large cities with low population densities. The maximum temperature (0.16°C vs 0.76°C, 0.04°C vs 0.87°C, and 0.09°C vs 0.91°C), change in temperature (0.24°C vs 0.90°C, 0.38°C vs 0.81°C, and 0.41°C vs 0.83°C), average atmospheric pressure (0.16 vs 0.52 hPa, 0.25 vs 0.42 hPa, 0.34 vs 0.40 hPa), and maximum atmospheric pressure (0.15 vs 0.53 hPa, 0.28 vs 0.49 hPa, 0.33 vs 0.71 hPa) were greater for Day 0, Day-1, and Day-2, respectively, in PD than in NPD. Meanwhile, the average (0.31 vs 0.48 m/s, 0.28 vs 0.46 m/s, 0.20 vs 0.40 m/s), minimum (0.20 vs 0.31 m/s, 0.18 vs 0.25 m/s, 0.16 vs 0.25 m/s), and maximum (0.44 vs 0.67 m/s, 0.36 vs 0.71 m/s, 0.26 vs 0.58 m/s) wind speeds were slower, and the changes in wind speed (0.44 vs 0.67 m/s, 0.36 vs 0.71 m/s, 0.16 vs 0.25 m/s) were lower for all 3 days in PD than in NPD. High average and change in temperature, slow and unchanging wind speed, and high average and maximum atmospheric pressure were associated with SP. Since many findings of this study were contradictory to previous studies, it is assumed that the interaction of various factors affects SP.

Effect of meteorological factors on first episode and recurrence of primary spontaneous pneumothorax

OBJECTIVE

In this study, we evaluated the clinical characteristics and seasonal distribution of patients with primary spontaneous pneumothorax and examined the relationships between meteorological factors and pneumothorax development overall and in terms of first episode and recurrence.

METHODS

The hospital records of 168 pneumothorax patients treated in our clinic between January 2016 and December 2020 were reviewed retrospectively. A cluster was defined as two or more patients with pneumothorax presenting within three consecutive days. Meteorological factors were compared between days with and without pneumothorax patients. This comparison was based on meteorological data from the day of symptom onset (D), the day before symptom onset (D1), and the difference between those days (D-D1). Meteorological data from the index day (D) were also compared between patients with first episode and recurrence of pneumothorax.

RESULTS

The study included 149 (88.7%) men and 19 (11.3%) women. The mean age was 25.02±6.97 (range, 17-35; median, 26) years. Of note, 73 (43.4%) patients underwent surgery. The highest number of patients presented in November (n=19, 11.3%). In terms of season, most presentations occurred in autumn. Humidity was significantly lower on recurrence days compared with first episode (p=0.041).

CONCLUSION

Our results indicated that meteorological factors (i.e., atmospheric pressure, humidity, wind speed, temperature, and precipitation) were not associated with pneumothorax development. By comparing the patients with first episode and recurrence, the humidity was significantly lower in the recurrence group.

Pneumothorax and the environment: A systematic review of the impact of air pollution and meteorology, and a meta-analysis on meteorology factors

A relationship between the occurrence of spontaneous pneumothorax (SP) and meteorological factors has been observed but with contradictory results. The objectives of this systematic review was to synthesis the current body of evidence to the relationships between the occurrence of SP and environmental determinants such as meteorological factors and air pollutants. We conducted a systematic search of MEDLINE, Scopus, Cochrane Library and gray literature from inception up to 31st December 2020, to find published scientific research articles based on the following eligibility criteria: original studies and population-based articles describing the relationship between meteorological factors or air pollutants and the occurrence of SP. For the meta-analysis, studies involving a quantitative analysis of the exposure variable (atmospheric pressure, temperature, humidity and wind speed) and the impact of the occurrence of SP with comparable methodology were selected. General characteristics and methodological information for each study were assessed. The quality was evaluated according to the Newcastle-Ottawa Scale. Fourty four and 13 studies were respectively included in the qualitative and quantitative analyses. The variability of the study design with moderate quality and the different measurements of the exposure variables highlight the contrasting results. The results of the meta-analyses are in favor of a higher temperature observed in the day with SP than in the days without SP (maximum: MD 0.25 (-0.08, 0.58) p = 0.14; I² = 26%, p = 0.21; mean: MD 0.22 (-0.15, 0.59) p = 0.24; I² = 45%, p = 0.07). The small number of studies focused on air pollution did not allow us to conclude to determine the potential impact of exposure to air pollutants on the occurrence of SP. Meteorological conditions seem to be related to SP occurrence, especially increased temperature.

Meteorological effects on severe hemoptysis: A hospital-based observational study

BACKGROUND

Although some meteorological factor are likely to contribute to the onset of hemoptysis, few studies have investigated this issue, with none conducted in the Asia-Pacific region. Therefore, the present study aimed to evaluate the associations of meteorological factors with the occurrence of hemoptysis. Differences in the frequency of hemoptysis among several calendar variables were also assessed.

METHODS

A total of 47 hemoptysis patients aged ≥ 20 years undergoing bronchial artery embolization in Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers from January 2012 to December 2017 were included in the study. All hemoptysis events were assembled in a single time series, and the proportion of hemoptysis days was 2.1%. The associations of meteorological variables with hemoptysis days were estimated as odds ratios with 95% confidence intervals by using multivariable-adjusted logistic regression models. The frequency of hemoptysis days was compared among several calendar variables using a chi-square test.

RESULTS

Mean relative humidity was negatively associated with hemoptysis (P for trend = 0.02). The inverse association remained significant when only the hemoptysis events with no infectious lung diseases were used (P for trend=0.02). No significant difference was observed in the occurrence of hemoptysis among seasons, months, or other calendar variables (all P ≥ 0.21).

CONCLUSIONS

Lower relative humidity was a significant risk factor for the development of hemoptysis. Clinicians should be aware of the potential for increases in hemoptysis events on days with low ambient humidity.