Why does rhinitis get worse in winter in the north?

Speaking of rhinitis, it is estimated that many people suffer from it, especially in the cold winter, when they feel like they can't live anymore... So how hard is winter for rhinitis patients? As I write this, my nose starts to itch, and I also think of the days when I was dominated by rhinitis in my hometown in the north. Especially in the mornings in winter, I start to sneeze as soon as I wake up, and I feel like I won't stop until the roof is blown off; you think that's the end, but no, no, no, after waiting for the sneezing to stop, you open the door and are greeted by the cold air, and your nose starts to produce runny nose; it's even worse in the classroom, and when it's serious, I almost want to give up my nose, it's really too painful.

Later, I came to live in the south and my rhinitis actually got better. But when winter comes, I can't help but think of the fear of being dominated by rhinitis during my student days.

In fact, I have always been curious about a question, why does rhinitis get worse in the north in winter? Who is the real culprit for the onset/aggravation of rhinitis in winter? In fact, haze and cold air are the two main causes of rhinitis. Let's talk about rhinitis today.

01. One of the main culprits: smog

The first culprit I found was smog. In fact, smog was a term that started to appear in the news 10 years later. At that time, I was already in the south, where smog was relatively rare, so I was very confused at the time, wondering how smog could suddenly appear.

Later, when I went back to my hometown, I saw the weather forecast saying that there would be heavy smog today. I was worried for a long time and was very curious about it. But when I got off the plane, I saw the foggy sky outside and smelled the thick smell of coal smoke in the air. I realized that this thing has always existed. I have lived in such a world since I was a child, but at that time people didn’t call it "smog".

Air pollution such as smog is an important factor in inducing or aggravating rhinitis. For example, a study found that for every 10 μg/m3 increase in PM10 in the air, the proportion of people visiting hospitals for rhinitis treatment increased by 0.79%. The factor behind this is air pollutants[1].

There are many particulate matter in air pollutants, which can be divided into PM1, PM2.5 and PM10 according to their size. After these particles enter the nasal cavity with breathing, they tend to accumulate in the nasal mucosa and other places. These particles are difficult to degrade, which will cause damage to the nasal mucosa and destroy the mucus blanket structure of the nose, making it difficult to remove these particles in time. The result of not being removed is that they are recognized by the human immune system, resulting in these allergens and mucosal immune cells continuing to react, causing rhinitis or worsening rhinitis.

This is also the reason why rhinitis worsens in smog weather. However, in addition to smog, weather is also an important factor affecting rhinitis.

02. The second culprit: cold air

Many people are curious about why rhinitis is more likely to occur in winter in the same place. In fact, it is caused by cold air.

The nasal cavity is the first step for air to enter the human body, so the nasal cavity itself is also very susceptible to temperature changes. In winter, the air is very dry and cold, so some people with weak nasal function are easily directly affected by the dry and cold air, which damages the epithelial cells of the nasal mucosa.

In addition, dry and cold air itself will stimulate the secretion of inflammatory factors in mast cells and immune cells. After all, responding to external changes is one of the basic functions of immunity, and as a result, the immunity of the nose will also be enhanced. In addition, in order to respond to dry and cold air, the blood vessels of the nasal mucosa will often increase the flow to improve the temperature. At this time, if you have rhinitis problems, you are more likely to get rhinitis.

Because of this, people with rhinitis should be more prepared on days with severe air pollution and when cold air strikes (in winter/air-conditioned rooms in summer), such as in winter. To sum it up in one sentence: "combining prevention and treatment, four-in-one" - avoiding allergens/triggers, standardizing drug treatment, physical therapy, and strengthening the study of rhinitis knowledge.

In fact, air pollution and cold air are only some of the factors that cause rhinitis. Rhinitis itself is a series of complex changes. Generally, clinical symptoms of nasal mucosal inflammation with the main characteristics of nasal congestion and runny nose are called rhinitis. Rhinitis is a very common disease with a very high incidence rate. In theory, men and women of all ages will encounter rhinitis in their daily lives.

03. Does rhinitis need treatment?

If it is short-term rhinitis or rhinitis caused by a cold, it can usually be relieved on its own, but if the rhinitis is severe enough to affect work and life, then treatment is required.

Because rhinitis affects a wide range of people, there are many drugs available in medicine to treat rhinitis. For example, the “Expert Consensus on the Classification and Diagnosis of Rhinitis and Nasal Medication Regimens” points out several common types of drugs for treating rhinitis [2].

The most common first-line medication is nasal glucocorticoids. Glucocorticoids are a type of technology secreted by the zona fasciculata of the adrenal cortex. Their chemical nature is steroidal. They are a drug with powerful anti-inflammatory effects. Therefore, they have become the main drug for treating rhinitis since their discovery.

The main mechanism of action of glucocorticoids is that they can bind to receptors, regulate the transcription of anti-inflammatory genes, reduce the expression of inflammatory genes, thereby directly exerting anti-inflammatory effects. At the same time, they can inhibit the processes of various inflammatory cells themselves, thereby alleviating rhinitis symptoms.

As the first-line medication, glucocorticoids are basically effective for various rhinitis symptoms, and therefore have become the first choice for the treatment of rhinitis.

Of course, in addition to nasal glucocorticoids, some other types of drugs have also been gradually used in recent years. For example, for allergic rhinitis, such as antihistamines, can relieve the release of histamine caused by rhinitis. Nasal decongestants are similar to antihistamines and can also relieve nasal congestion symptoms. In addition, some physical methods such as washing with saline to flush foreign irritants from the nasal mucosa also have a certain effect on alleviating symptoms.

In fact, as a common disease, rhinitis actually has many clinical treatment methods. Many people think that they can just endure it and it will end. As a result, rhinitis persists for a long time. This is not a good strategy. Since there are many clinical solutions, timely standardized treatment is still the first choice.

Of course, for patients with rhinitis, it is currently the middle of winter, and wearing a mask and reducing going out is a good way to prevent intermittent epidemics.

1 Burte, Emilie, et al. "Long-term air pollution exposure is associated with increased severity of rhinitis in 2 European cohorts." Journal of allergy and clinical immunology 145.3 (2020): 834-842.

2 Li Huabin, Wang Xiangdong, Wang Hongtian, Tan Guolin, Chen Jianjun, Xu Rui, Meng Juan, Zhang Weitian, Yang Qintai, Qiu Qianhui, Tang Jun, Ye Jing, Meng Cuida, Xu Yuanteng, Yu Shaoqing, Xie Zhihai, Xu Chengli, Sun Bin, Yang Yucheng, Zhang Tianhong, Yu Guodong, Wang Dehui. Expert consensus on the classification and diagnosis of rhinitis and nasal medication regimens[J]. Chinese Journal of Otorhinolaryngology and Skull Base Surgery, 2019, 25(06): 573-577.