Reference: Fataawa Ramadhaan – Volume 1, Page 251, Fatwa No.199
Question: I inform your eminence that I am a man of 80 years of age, and I am afflicted by an illness of the arteries and the heart. I was unable to fast the month of Ramadhaan last year – 1404 AH (1984 AD), so I set about giving three sacks of wheat to three poor and needy families we have in our village; The three sacks roughly equated to 34 mudd. As for this year, then I do not know if I will be able to fast or not, [only] Allaah has the complete knowledge [of all affairs]. For this reason I ask that you provide me with a religious verdict regarding that which I have mentioned, since I will remain ill at ease until I receive your religious verdict regarding that.
Response: If the situation is as mentioned, that you are indeed 80 years of age and are afflicted by an illness of the arteries and the heart, and that you did not fast last Ramadhaan due to your inability, then there is no harm in you not fasting [this Ramadhaan]. [Additionally], it is sufficient for you, as compensation, to feed one poor and needy person for every day you are unable to fast half a saa’ – which approximates to one and a half kilograms of rice or wheat or the likes of that which is consumed in your country.
And with Allaah lies all the success, and may Allaah send prayers and salutations upon our Prophet Muhammad ﷺ and his family and his companions.