Abstract
Objective
We aimed to investigate the impacts of prolonged mask use on patients with hypertension or diabetes during the COVID-19 pandemic.
Methods
This study included patients with hypertension or diabetes who visited the outpatient department of Nanjing Yimin Hospital between 1 February 2022 and 31 January 2023. We compared the change in blood pressure (BP) and fasting plasma glucose in patients with hypertension or diabetes and adjustments to treatment between the group with prolonged mask-wearing group (≥20 hours/week) and the control group (<20 hours/week).
Results
Compared with the control group of hypertensive patients, the prolonged mask-wearing group had significantly higher diastolic blood pressure (DBP) and mean arterial pressure (MAP). These two groups had had similar DBP and MAP 1 year earlier. Likewise, the prolonged mask-wearing group of patients with diabetes had a greater need than the control group for upgraded treatment to reach their therapeutic goals.
Conclusions
This study suggests that prolonged mask use by patients with hypertension or diabetes has negative effects on hypertension and plasma glucose control. BP and plasma glucose monitoring should be improved in these patient populations and their treatment should be adjusted in a timely manner.
Keywords: Prolonged mask-wearing, hypertension, diabetes, blood pressure, fasting plasma glucose, monitoring
Introduction
Since the end of 2019, coronavirus disease 2019 (COVID-19) has spread across the globe and caused severe health problems worldwide. According to the World Health Organization (WHO), as of 25 June 2023, over 767 million confirmed cases and over 6.9 million deaths have been reported globally (https://www.who.int/publications/m/item/weekly-epidemiological-update-on-covid-19—29-june-2023). However, the actual toll might be far higher than these numbers. The pandemic has profoundly changed the lifestyles of people worldwide. For individuals, maintaining a safe distance, handwashing, and wearing masks in public places are the main steps to prevent COVID-19 infection. Among these steps, mask-wearing plays a key role in reducing the transmission of SARS-CoV-2, the virus that causes COVID-19.
Although the WHO formally announced the end of the pandemic on 5 May 2023, the agency warned that humans will coexist with SARS-CoV-2 for a very long time. Studies have shown that compared with healthy people, patients who have chronic diseases, such as hypertension and diabetes, often have more severe symptoms and a higher mortality rate when infected with SARS-CoV-2.1,2 To prevent initial or repeat infection, many patients with hypertension or diabetes continue to wear masks in public places, especially in China.3,4
Wearing a mask may evoke many types of discomfort and lead to acute or chronic effects such as chest tightness, shortness of breath, anxiety, and palpitation. Bao et al. 5 asked healthy individuals to continuously wear an N95 mask and observed the effects, which included a significantly increased heart rate after 1 hour of mask-wearing, significantly increased blood pressure (BP) after light exercise, and significantly increased plasma levels of norepinephrine and methoxyadrenaline after 14 hours of mask-wearing. It remains unclear whether wearing a mask for a long period can adversely affect BP in patients with hypertension and plasma glucose in those with diabetes, or whether mask-wearing makes it more challenging for these patients to control their BP and plasma glucose. The actual impact of prolonged mask-wearing on patients with hypertension or diabetes have not been evaluated. In the present clinical research, we delve into the effects of prolonged mask-wearing on BP and fasting plasma glucose among Chinese patients with hypertension or diabetes, respectively.
Methods
Participant screening
This was a case–control study. The present clinical investigation was conducted among outpatients with hypertension or diabetes who registered at Nanjing Yimin Hospital from 1 February 2022 to 31 January 2023. To be eligible, candidates had to meet the following criteria: (1) aged between 18 and 80 years; (2) a clearly diagnosed history of hypertension or diabetes for more than 1 year; (3) outpatient medical records clearly indicating the patient’s BP or fasting plasma glucose value and the treatment plan 1 year before the candidate was recruited; (4) no other underlying severe diseases, such as advanced tumors, chronic obstructive pulmonary disease (COPD), or blood diseases; (5) willing to complete a survey administered by outpatient doctors. All patients used surgical masks that complied with the YY0469-2011 standard and had no past history of COVID-19 infection.
Data collection
Outpatient doctors collected patients’ information, including basic BP, fasting plasma glucose, and treatments at the time of the hospital visit and 1 year earlier, as well as mask-wearing information, including the daily time (hours) of mask-wearing, number of days per week of mask-wearing, and total time (hours) of mask-wearing. The outpatient physicians determined whether each patient had required an upgrade to their anti-hypertensive or hypoglycemic treatment during the past year so as to reach their therapeutic goals.
Groups and observation
Patients who wore a mask for 20 hours or more per week were included in the prolonged mask-wearing group (study group), and patients who wore a mask for less than 20 hours per week were included in the control group. The changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) over the previous year in the study group of hypertensive patients were compared with those in the control group of hypertensive patients, and upgrades to treatments were monitored. We compared changes in fasting plasma glucose over the past year in the study group of patients with diabetes with those in the control group of patients with diabetes. Upgrades to treatment were also monitored in patients with diabetes.
Ethics statement
This study was conducted in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Nanjing Yimin Hospital (NJYMH Ethics No. 2, 7 January 2022). Written informed consent was obtained from all participants involved in the study.
Statistical analysis
We used IBM SPSS 21.0 (IBM Corp., Armonk, NY, USA) for the data analysis. All continuous variables were tested for a normal distribution and homogeneity of variance, and the data were in line with a normal distribution. The results are described using mean ± standard deviation, and the differences between two groups were tested using an independent t-test. Frequency data are reported as counts in each group (n), and comparisons between frequency data groups were tested using Pearson’s chi-square test and Fisher’s exact test. In this study, two-sided P < 0.05 was considered statistically significant. Statistical analyses for figures were performed using GraphPad Prism 9.0 (GraphPad Software Inc., San Diego, CA, USA). We used a two-way analysis of variance in conjunction with Šidák’s multiple comparisons test for two time points (1 year before the hospital visit and at the time of the hospital visit 1 year later) and overall differences between the two mask-wearing groups (Figures 1a–1c, 2a, and 2c) and a Fisher’s exact test (Figures 1d, 2b, and 2d).
Figure 1.
Effects of prolonged mask-wearing in hypertensive patients. (a–c) Comparison of systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) between the prolonged mask-wearing group and control group of hypertensive patients, respectively and (d) Comparison of the proportion needing upgraded treatment between the prolonged mask-wearing group and control group of hypertensive patients. NS, not significant. *P < 0.05; ****P < 0.0001. All error bars represent standard error of the mean.
Figure 2.
Effects of prolonged mask-wearing on patients with diabetes. (a) Comparison of fasting blood glucose (FBG) between the prolonged mask-wearing group and control group of patients with diabetes. (b) Comparison of the proportion needing upgraded treatment between the prolonged mask-wearing group and control group of patients with diabetes. (c) Comparison of FBG between the prolonged mask wearing group and control group in the subgroup of patients with diabetes and well-controlled FBG 1 year earlier and (d) Comparison of the proportion needing upgraded treatment between the prolonged mask-wearing group and control group in the subgroup of patients with diabetes and well-controlled FBG 1 year earlier. NS, not significant. *P < 0.05; ****P < 0.0001. All error bars represent standard error of the mean.
This research was reported according to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guideline. 6 All patient details have been de-identified.
Results
A total of 206 patients were enrolled, including 85 in the hypertension group (55 male and 30 female patients) and 121 in the diabetes group (94 male and 27 female patients). Among patients with hypertension (n = 85), the prolonged mask-wearing group (n = 54) had a weekly mask-wearing time of 40.57 ± 8.86 hours, which was significantly higher than that of the control group (n = 31), at 10.14 ± 3.32 hours (P < 0.001) (Table 1). Compared with the control group, the prolonged mask-wearing group had significantly higher DBP and MAP (85.87 ± 6.75 mmHg vs. 80.52 ± 7.85 mmHg and 101.82 ± 7.51 mmHg vs. 96.87 ± 7.58 mmHg, respectively; P < 0.05). The two groups had similar DBP and MAP 1 year prior to the hospital visit (Table 1 and Figure 1a–1c). The proportion of patients requiring an upgrade to their treatment was not significantly different between the two groups (Table 1 and Figure 1d).
Table 1.
Effects of prolonged mask-wearing on hypertensive patients.
| Mask-wearing<20 hours/week (n = 31) | Mask-wearing≥20 hours/week (n = 54) | P | |
|---|---|---|---|
| Age (years) | 67.00 ± 9.79 | 51.30 ± 10.14 | <0.001* |
| Sex | 0.332 | ||
| Male (n) | 18 | 37 | |
| Female (n) | 13 | 17 | |
| BMI (kg/m2) | 24.96 ± 2.78 | 24.99 ± 2.26 | 0.966 |
| Duration of hypertension (years) | 11.36 ± 10.96 | 8.19 ± 7.92 | 0.127 |
| Mask-wearing per week (hours) | 10.16 ± 3.32 | 40.57 ± 8.86 | <0.001* |
| SBP 1 year earlier (mmHg) | 163.16 ± 21.86 | 154.63 ± 16.43 | 0.045* |
| DBP 1 year earlier (mmHg) | 96.77 ± 15.45 | 96.24 ± 12.57 | 0.863 |
| MAP 1 year earlier (mmHg) | 118.90 ± 16.03 | 115.72 ± 11.76 | 0.297 |
| SBP currently (mmHg) | 129.58 ± 9.42 | 133.57 ± 11.70 | 0.109 |
| DBP currently (mmHg) | 80.52 ± 7.85 | 85.87 ± 6.75 | 0.001* |
| MAP currently (mmHg) | 96.87 ± 7.58 | 101.82 ± 7.51 | 0.005* |
| Medication adjustment | 0.297 | ||
| Upgraded treatment (n) | 5 | 14 | |
| No upgraded treatment (n) | 26 | 40 |
BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; MAP, mean arterial pressure. *P < 0.05.
In patients with diabetes (n = 121), the prolonged mask-wearing group (n = 90) had a weekly mask-wearing time of 37.14 ± 14.71 hours, which was significantly higher than that of the control group (n = 31, 14.02 ± 3.47 hours, P < 0.001). Patients with diabetes in the prolonged mask-wearing group and the control group had similar levels of plasma glucose after 1 year of mask-wearing (Table 2 and Figure 2a). However, the prolonged mask-wearing group had a greater need for upgraded treatment to reach their therapeutic goals than the control group (Table 2 and Figure 2b). Similar results were detected in patients with diabetes who had well-controlled fasting plasma glucose 1 year before the hospital visit (Table 3 and Figure 2c and 2d).
Table 2.
Effects of prolonged mask-wearing on patients with diabetes.
| Mask-wearing<20 hours/week (n = 31) | Mask-wearing≥20 hours/week (n = 90) | P | |
|---|---|---|---|
| Age (y) | 59.65 ± 11.57 | 54.80 ± 9.56 | 0.023* |
| Sex | 0.041* | ||
| Male (n) | 20 | 74 | |
| Female (n) | 11 | 16 | |
| BMI (kg/m2) | 25.18 ± 3.51 | 25.05 ± 2.69 | 0.829 |
| Duration of diabetes (years) | 9.45 ± 6.30 | 7.26 ± 5.53 | 0.068 |
| Mask-wearing per week (hours) | 14.02 ± 3.47 | 37.14 ± 14.71 | <0.001* |
| FBG 1 year earlier (mmol/L) | 7.89 ± 2.14 | 9.06 ± 2.44 | 0.019* |
| FBG currently (mmol/L) | 7.32 ± 2.47 | 7.07 ± 1.02 | 0.438 |
| Medication adjustment | <0.001* | ||
| Upgraded treatment (n) | 6 | 54 | |
| No upgraded treatment (n) | 25 | 36 |
BMI, body mass index; FBG, fasting blood glucose. *P < 0.05.
Table 3.
Effects of prolonged mask-wearing on subgroup of patients with diabetes and normal FBG 1 year earlier.
| Mask-wearing<20 hours/week (n = 18) | Mask-wearing≥20 hours/week (n = 20) | P | |
|---|---|---|---|
| Age (years) | 61.61 ± 11.60 | 54.10 ± 7.93 | 0.024* |
| Sex | 0.003* | ||
| Male (n) | 11 | 20 | |
| Female (n) | 7 | 0 | |
| BMI (kg/m2) | 24.58 ± 2.34 | 24.77 ± 2.19 | 0.797 |
| Duration of diabetes (years) | 9.50 ± 5.06 | 7.50 ± 5.75 | 0.265 |
| Mask-wearing per week (hours) | 12.94 ± 3.00 | 40.50 ± 15.08 | <0.001* |
| FBG 1 year earlier (mmol/L) | 6.61 ± 0.21 | 6.71 ± 0.30 | 0.231 |
| FBG currently (mmol/L) | 6.61 ± 0.22 | 7.14 ± 1.29 | 0.098 |
| Medication adjustment | 0.021* | ||
| Upgraded treatment (n) | 0 | 6 | |
| No upgraded treatment (n) | 18 | 14 |
BMI, body mass index; FBG, fasting blood glucose. *P < 0.05.
Discussion
China has an enormous number of patients with hypertension or diabetes, most of whom are older. To reduce the risk of COVID-19 infection, most of these patients continue to wear a mask in public places. Some patients with hypertension or diabetes complain that prolonged mask-wearing causes chest tightness, palpitation, dizziness, and other uncomfortable symptoms. We therefore designed and conducted this study to investigate whether prolonged mask-wearing affects BP and blood glucose in patients with hypertension or diabetes. We found that prolonged mask-wearing had significantly adverse effects on both patients with hypertension as well as those with diabetes.
The harmful physiological effects of prolonged mask-wearing on humans cannot be ignored.7,8 Kim et al. 9 asked healthy subjects to wear N95 masks for 10 minutes and found that participants’ oxygen saturation was decreased when compared with that before wearing a mask. Doherty et al. 10 reported that healthy people’s carbon dioxide levels were significantly increased after exercising while wearing a mask. Kampert et al. 11 found that healthy people’s respiratory resistance increased significantly after running on a treadmill at peak power with a face mask on. Fikenzer et al. 12 conducted a prospective crossover study among 12 healthy participants and reported that the mask-wearing group (regardless of whether a normal surgical mask or N95 mask was worn) had significant reductions in both forced lung capacity and maximum expiratory flow rate after a cardiopulmonary exercise test. These studies indicate that wearing a mask, especially for a long time, has different degrees of adverse effects on the respiratory and cardiovascular circulatory system.
Wearing a face mask has an adverse effect on patients with hypertension or diabetes for the following possible reasons:13–15 First, psychological effects probably play a pivotal role. Many people have an intrinsic repulsion toward wearing a mask because the mask feels uncomfortable. Wearing a face mask for a long time leads to poor breathing, tension, and even anxiety. Sympathetic nerve excitation causes increased glucagon secretion, leading to increased blood sugar levels and catecholamine secretion, which causes peripheral vasoconstriction. Second, wearing a mask can lead to air hunger, frequent deep breathing, increased work to breathe, compensation for accelerated blood flow, and increased cardiac output and liver glycogen decomposition, which eventually cause raised BP and blood glucose. Finally, wearing a face mask for a long time and/or repeatedly stimulates these processes, resulting in a long-lasting increase in blood glucose and BP.
Although there have been no studies on the effects of mask-wearing among patients with hypertension or diabetes, some investigators have noted that wearing a face mask seems to greatly impact COPD, another common disease globally.16–18 The larger the enclosed space between the mask and the face, the greater the amount of extra dead space and the greater the risk of hypoxia and carbon dioxide retention in patients with COPD. 19 COPD is a systemic disease caused by chronic hypoxia in the body for a long period, which is often complicated by hypertension or diabetes. The impact of mask-wearing on patients with COPD as well as those with hypertension or diabetes require greater attention.
This study suggested that prolonged mask-wearing has adverse effects on both patients with hypertension and those with diabetes. However, some limitations of this study should be noted. First, the data in this study came from one hospital and a relatively small sample; thus, the data are not universally representative. Second, among recruited patients with hypertension or diabetes, a very high proportion had poorly controlled BP or blood glucose 1 year earlier (especially hypertensive patients), possibly owing to the difficulty in attending hospital visits and irregular medication use during the COVID-19 pandemic. Therefore, we could not compare BP changes in the subgroup of patients with well-controlled BP 1 year earlier because the sample was too small. Further studies should expand the sample size and include patients with well-controlled basic BP and blood glucose to reduce bias. Third, there are a lack of data on potential confounding variables in our study, such as exercise and healthy diet.
In conclusion, this clinical study showed that prolonged mask-wearing has substantial adverse effects on BP and blood glucose control in patients with hypertension and diabetes, respectively. This situation requires greater clinical attention. In the post-pandemic era, if hypertensive patients and patients with diabetes must wear a mask for a long period, strengthened BP and plasma glucose monitoring as well as timely adjustment to treatment are needed for these patients.
Supplemental Material
Supplemental material, sj-pdf-1-imr-10.1177_03000605241232946 for Effects of prolonged face mask use among patients with hypertension or diabetes during the COVID-19 pandemic by Weiwei He, Yang Liu, Zhaoting Zou, Chunbao Cheng, Wenjing Wang, Zhixin Huang, Guannan Wu, Weiquan Zhu and Huiming Sun in Journal of International Medical Research
Supplemental material, sj-pdf-2-imr-10.1177_03000605241232946 for Effects of prolonged face mask use among patients with hypertension or diabetes during the COVID-19 pandemic by Weiwei He, Yang Liu, Zhaoting Zou, Chunbao Cheng, Wenjing Wang, Zhixin Huang, Guannan Wu, Weiquan Zhu and Huiming Sun in Journal of International Medical Research
Author contributions: Conceptualization: Y Liu and HM Sun; methodology: HM Sun; validation: HM Sun; formal analysis: Y Liu, GN Wu, WQ Zhu, and HM Sun; investigation: ZT Zou and CB Cheng; resources: HM Sun; data curation: WW He, Y Liu, WJ Wang, ZX Huang, WQ Zhu, and HM Sun; writing—original draft preparation: WW He and Y Liu; writing—review and editing: WQ Zhu and HM Sun; supervision: WQ Zhu and HM Sun; project administration: HM Sun. All authors have read and agreed to the published version of the manuscript.
The authors declare that there is no conflict of interest.
Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.
ORCID iD: Huiming Sun https://orcid.org/0000-0003-3438-6004
Data availability statement
The data in this study are available on request from the corresponding author. The data are not publicly available owing to limitations of ethical approval involving patient data and anonymity.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Supplemental material, sj-pdf-1-imr-10.1177_03000605241232946 for Effects of prolonged face mask use among patients with hypertension or diabetes during the COVID-19 pandemic by Weiwei He, Yang Liu, Zhaoting Zou, Chunbao Cheng, Wenjing Wang, Zhixin Huang, Guannan Wu, Weiquan Zhu and Huiming Sun in Journal of International Medical Research
Supplemental material, sj-pdf-2-imr-10.1177_03000605241232946 for Effects of prolonged face mask use among patients with hypertension or diabetes during the COVID-19 pandemic by Weiwei He, Yang Liu, Zhaoting Zou, Chunbao Cheng, Wenjing Wang, Zhixin Huang, Guannan Wu, Weiquan Zhu and Huiming Sun in Journal of International Medical Research
Data Availability Statement
The data in this study are available on request from the corresponding author. The data are not publicly available owing to limitations of ethical approval involving patient data and anonymity.